VM pageout scalability improvements
Subsystems (20)
cover VM pageout scalability improvements
On large memory systems, the VM can spend way too much time scanning through pages that it cannot (or should not) evict from memory. Not only does it use up CPU time, but it also provokes lock contention and can leave large systems under memory presure in a catatonic state.
Against 2.6.24-rc6-mm1
This patch series improves VM scalability by:
1) making the locking a little more scalable
2) putting filesystem backed, swap backed and non-reclaimable pages onto their own LRUs, so the system only scans the pages that it can/should evict from memory
3) switching to SEQ replacement for the anonymous LRUs, so the number of pages that need to be scanned when the system starts swapping is bound to a reasonable number
More info on the overall design can be found at:
http://linux-mm.org/PageReplacementDesign
Changelog:
- merge memcontroller split LRU code into the main split LRU patch, since it is not functionally different (it was split up only to help people who had seen the last version of the patch series review it)
- drop the page_file_cache debugging patch, since it never triggered
- reintroduce code to not scan anon list if swap is full
- add code to scan anon list if page cache is very small already
- use lumpy reclaim more aggressively for smaller order > 1 allocations
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 1/19 move isolate_lru_page() to vmscan.c
V1 -> V2 [lts]:
+ fix botched merge -- add back "get_page_unless_zero()"
From: Nick Piggin <[email protected]>
To: Linux Memory Management <[email protected]>
Subject: [patch 1/4] mm: move and rework isolate_lru_page
Date: Mon, 12 Mar 2007 07:38:44 +0100 (CET)
isolate_lru_page logically belongs to be in vmscan.c than migrate.c.
It is tough, because we don't need that function without memory migration so there is a valid argument to have it in migrate.c. However a subsequent patch needs to make use of it in the core mm, so we can happily move it to vmscan.c.
Also, make the function a little more generic by not requiring that it adds an isolated page to a given list. Callers can do that.
Note that we now have '__isolate_lru_page()', that does something quite different, visible outside of vmscan.c for use with memory controller. Methinks we need to
rationalize these names/purposes. --lts
include/linux/migrate.h +0 -3
@@ -25,7 +25,6 @@ static inline int vma_migratable(structreturn 1 ; } -extern int isolate_lru_page (struct page *p,struct list_head *pagelist);extern int putback_lru_pages (struct list_head *l);extern int migrate_page (struct address_space *,struct page *,struct page *);
@@ -42,8 +41,6 @@ extern int migrate_vmas(struct mm_structstatic inline int vma_migratable (struct vm_area_struct *vma) {return 0 ; } -static inline int isolate_lru_page (struct page *p,struct list_head *list) - {return -ENOSYS ; }static inline int putback_lru_pages (struct list_head *l) {return 0 ; }static inline int migrate_pages (struct list_head *l,new_page_t x,unsigned long private) {return -ENOSYS ; }
mm/internal.h +2 -0
@@ -34,6 +34,8 @@ static inline void __put_page(struct pagatomic_dec (&page->_count); } +extern int isolate_lru_page (struct page *page); +extern void __init __free_pages_bootmem (struct page *page,unsigned int order);
mm/migrate.c +10 -37
60 lines not on this page · raw message
mm/vmscan.c +41 -0
47 lines not on this page · raw message
mm/mempolicy.c +8 -2
@@ -93,6 +93,8 @@#include <asm/tlbflush.h> #include <asm/uaccess.h> +#include "internal.h" +/* Internal flags */ #define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0)/* Skip checks for continuous vmas */ #define MPOL_MF_INVERT (MPOL_MF_INTERNAL << 1)/* Invert check for nodemask */
@@ -603,8 +605,12 @@ static void migrate_page_add(struct page/* * Avoid migrating a page that is shared with others. */ -if ((flags &MPOL_MF_MOVE_ALL ) ||page_mapcount (page) ==1 ) -isolate_lru_page (page, pagelist); +if ((flags &MPOL_MF_MOVE_ALL ) ||page_mapcount (page) ==1 ) { +if (!isolate_lru_page (page)) { +get_page (page); +list_add_tail (&page->lru, pagelist); + } + } }static struct page *new_node_page (struct page *page,unsigned long node,int **x)
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 01/19] move isolate_lru_page() to vmscan.c
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 2/19 free swap space on swap-in/activation
In reply to Rik van Riel+ lts' convert anon_vma list lock to reader/write lock patch
+ Nick Piggin's move and rework isolate_lru_page() patch
Free swap cache entries when swapping in pages if vm_swap_full() [swap space > 1/2 used?]. Uses new pagevec to reduce pressure on locks.
mm/vmscan.c +7 -0
@@ -632,6 +632,9 @@ free_it:continue ; activate_locked: +/* Not a candidate for swapping, so reclaim swap space. */ +if (PageSwapCache (page) &&vm_swap_full ()) +remove_exclusive_swap_page (page);SetPageActive (page); pgactivate++; keep_locked:
@@ -1214,6 +1217,8 @@ static void shrink_active_list(unsigned__mod_zone_page_state (zone,NR_ACTIVE , pgmoved); pgmoved =0 ;spin_unlock_irq (&zone->lru_lock); +if (vm_swap_full ()) +pagevec_swap_free (&pvec);__pagevec_release (&pvec);spin_lock_irq (&zone->lru_lock); }
@@ -1223,6 +1228,8 @@ static void shrink_active_list(unsigned__count_zone_vm_events (PGREFILL , zone, pgscanned);__count_vm_events (PGDEACTIVATE , pgdeactivate);spin_unlock_irq (&zone->lru_lock); +if (vm_swap_full ()) +pagevec_swap_free (&pvec);pagevec_release (&pvec); }
mm/swap.c +18 -0
@@ -465,6 +465,24 @@ void pagevec_strip(struct pagevec *pvec) } } +/* +* Try to free swap space from the pages in a pagevec +*/ +void pagevec_swap_free (struct pagevec *pvec) +{ +int i; + +for (i =0 ; i <pagevec_count (pvec); i++) { +struct page *page = pvec->pages[i]; + +if (PageSwapCache (page) && !TestSetPageLocked (page)) { +if (PageSwapCache (page)) +remove_exclusive_swap_page (page); +unlock_page (page); + } + } +} +/** * pagevec_lookup - gang pagecache lookup * @pvec: Where the resulting pages are placed
include/linux/pagevec.h +1 -0
@@ -26,6 +26,7 @@ void __pagevec_free(struct pagevec *pvecvoid __pagevec_lru_add (struct pagevec *pvec);void __pagevec_lru_add_active (struct pagevec *pvec);void pagevec_strip (struct pagevec *pvec); +void pagevec_swap_free (struct pagevec *pvec);unsigned pagevec_lookup (struct pagevec *pvec,struct address_space *mapping,pgoff_t start,unsigned nr_pages); unsigned pagevec_lookup_tag(struct pagevec *pvec,
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 02/19] free swap space on swap-in/activation
Quoted 3 lines · Rik van Riel
Free swap cache entries when swapping in pages if
vm_swap_full()[swap space > 1/2 used?]. Uses new pagevec to reduce pressure on locks.
The pagevec function would be faster if the swap removal could be batched inside of the locks taken in remove_exclusive_swap_page.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 3/19 define page_file_cache() function
In reply to Rik van RielDefine page_file_cache() function to answer the question:
is page backed by a file?
Originally part of Rik van Riel's split-lru patch. Extracted to make available for other, independent reclaim patches.
Moved inline function to linux/mm_inline.h where it will be needed by subsequent "split LRU" and "noreclaim" patches.
Unfortunately this needs to use a page flag, since the PG_swapbacked state needs to be preserved all the way to the point where the page is last removed from the LRU. Trying to derive the status from other info in the page resulted in wrong VM statistics in earlier split VM patchsets.
include/linux/mm_inline.h +22 -0
@@ -1,3 +1,24 @@ +#ifndef LINUX_MM_INLINE_H +#define LINUX_MM_INLINE_H + +/** +* page_file_cache(@page) +* Returns !0 if @page is page cache page backed by a regular filesystem, +* or 0 if @page is anonymous, tmpfs or otherwise ram or swap backed. +* +* We would like to get this info without a page flag, but the state +* needs to survive until the page is last deleted from the LRU, which +* could be as far down as __page_cache_release. +*/ +static inline int page_file_cache (struct page *page) +{ +if (PageSwapBacked (page)) +return 0 ; + +/* The page is page cache backed by a normal filesystem. */ +return 2 ; +} +static inline void add_page_to_active_list (struct zone *zone,struct page *page) {
@@ -38,3 +59,4 @@ del_page_from_lru(struct zone *zone, str } } +#endif
mm/shmem.c +1 -0
@@ -1377,6 +1377,7 @@ repeat: goto failed; } +SetPageSwapBacked (filepage);spin_lock (&info->lock); entry =shmem_swp_alloc (info, idx, sgp);if (IS_ERR (entry))
include/linux/page-flags.h +5 -0
@@ -89,6 +89,7 @@#define PG_mappedtodisk 16/* Has blocks allocated on-disk */ #define PG_reclaim 17/* To be reclaimed asap */ #define PG_buddy 19/* Page is free, on buddy lists */ +#define PG_swapbacked 20/* Page is backed by RAM/swap */ /* PG_readahead is only used for file reads; PG_reclaim is only for writes */ #define PG_readahead PG_reclaim/* Reminder to do async read-ahead */
@@ -216,6 +217,10 @@ static inline void SetPageUptodate(struc#define ClearPageReclaim (page) clear_bit(PG_reclaim, &(page)->flags)#define TestClearPageReclaim (page) test_and_clear_bit(PG_reclaim, &(page)->flags) +#define PageSwapBacked (page) test_bit(PG_swapbacked, &(page)->flags) +#define SetPageSwapBacked (page) set_bit(PG_swapbacked, &(page)->flags) +#define __ClearPageSwapBacked (page) __clear_bit(PG_swapbacked, &(page)->flags) +#define PageCompound (page) test_bit(PG_compound, &(page)->flags)#define __SetPageCompound (page) __set_bit(PG_compound, &(page)->flags)#define __ClearPageCompound (page) __clear_bit(PG_compound, &(page)->flags)
mm/memory.c +3 -0
@@ -1664,6 +1664,7 @@ gotten:ptep_clear_flush (vma, address, page_table);set_pte_at (mm, address, page_table, entry);update_mmu_cache (vma, address, entry); +SetPageSwapBacked (new_page);lru_cache_add_active (new_page);page_add_new_anon_rmap (new_page, vma, address);
@@ -2131,6 +2132,7 @@ static int do_anonymous_page(struct mm_sif (!pte_none (*page_table)) goto release;inc_mm_counter (mm, anon_rss); +SetPageSwapBacked (page);lru_cache_add_active (page);page_add_new_anon_rmap (page, vma, address);set_pte_at (mm, address, page_table, entry);
@@ -2284,6 +2286,7 @@ static int __do_fault(struct mm_struct *set_pte_at (mm, address, page_table, entry);if (anon) {inc_mm_counter (mm, anon_rss); +SetPageSwapBacked (page);lru_cache_add_active (page);page_add_new_anon_rmap (page, vma, address); }else {
mm/swap_state.c +1 -0
@@ -82,6 +82,7 @@ int add_to_swap_cache(struct page *page,if (!error) {page_cache_get (page);SetPageSwapCache (page); +SetPageSwapBacked (page);set_page_private (page, entry.val); total_swapcache_pages++;__inc_zone_page_state (page,NR_FILE_PAGES );
mm/migrate.c +2 -0
@@ -546,6 +546,8 @@ static int move_to_new_page(struct page/* Prepare mapping for the new page.*/ newpage->index = page->index; newpage->mapping = page->mapping; +if (PageSwapBacked (page)) +SetPageSwapBacked (newpage); mapping =page_mapping (page);if (!mapping)
mm/page_alloc.c +4 -0
@@ -253,6 +253,7 @@ static void bad_page(struct page *page)1 << PG_slab |1 << PG_swapcache |1 << PG_writeback | +1 << PG_swapbacked | 1 << PG_buddy );set_page_count (page,0 );reset_page_mapcount (page);
@@ -485,6 +486,8 @@ static inline int free_pages_check(strucbad_page (page);if (PageDirty (page))__ClearPageDirty (page); +if (PageSwapBacked (page)) +__ClearPageSwapBacked (page);/* * For now, we report if PG_reserved was found set, but do not * clear it, and do not free the page. But we shall soon need
@@ -631,6 +634,7 @@ static int prep_new_page(struct page *pa 1 << PG_swapcache | 1 << PG_writeback | 1 << PG_reserved | + 1 << PG_swapbacked | 1 << PG_buddy ))))bad_page (page);
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 03/19] define page_file_cache() function
include/linux/mm_inline.h line 16
Quoted 7 lines · Rik van Riel
Define
page_file_cache()function to answer the question:
is page backed by a file?include/linux/mm_inline.h +4
-0+static inline int page_file_cache (struct page *page) +{ +if (PageSwapBacked (page)) +return 0 ;
Could we call this PageNotFileBacked or so? PageSwapBacked is true for pages that are RAM based. Its a bit confusing.
mm/migrate.c static int move_to_new_page(struct page · line 553
Quoted 13 lines
Index:
linux-2.6.24-rc6-mm1/mm/migrate.c
===================================================================mm/migrate.c +2
-0@@ -546,6 +546,8 @@ static int move_to_new_page(struct page/* Prepare mapping for the new page.*/ newpage->index = page->index; newpage->mapping = page->mapping; +if (PageSwapBacked (page)) +SetPageSwapBacked (newpage); mapping =page_mapping (page);if (!mapping)
That hunk belongs into migrate_page_copy()? Or is there a reason that we need this flag that early?
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 03/19] define page_file_cache() function
Quoted 5 lines · On Tue, 8 Jan 2008 14:18:40 -0800 (PST) Christoph Lameter <[email protected]>…
Quoted 2 lines · Rik van Riel
Define
page_file_cache()function to answer the question:
is page backed by a file?
Quoted 7 lines
include/linux/mm_inline.h line 16
Quoted 4 lines
include/linux/mm_inline.h +4
-0+static inline int page_file_cache (struct page *page) +{ +if (PageSwapBacked (page)) +return 0 ;Could we call this PageNotFileBacked or so? PageSwapBacked is true for pages that are RAM based. Its a bit confusing.
PageNotFileBacked confuses me a little, since shared memory segments live in tmpfs and are kinda sorta file backed, but go to swap instead of to a filesystem when there is memory pressure.
I'm always open to better naming ideas, though.
Quoted 11 lines
Quoted 11 lines
Index:
linux-2.6.24-rc6-mm1/mm/migrate.c
===================================================================mm/migrate.c +2
-0@@ -546,6 +546,8 @@ static int move_to_new_page(struct page/* Prepare mapping for the new page.*/ newpage->index = page->index; newpage->mapping = page->mapping; +if (PageSwapBacked (page)) +SetPageSwapBacked (newpage);
Quoted 5 lines
mm/migrate.c static int move_to_new_page(struct page · line 553
Quoted 2 lines
mm/migrate.c +0
-0mapping =page_mapping (page);if (!mapping)That hunk belongs into
migrate_page_copy()? Or is there a reason that we need this flag that early?
We want the page added to the right LRU list. I'll have to re-read the migration code to make sure whether the above can or cannot be done in migrate_page_copy() - I agree it would fit in better there.
Thanks for the suggestions.
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 03/19] define page_file_cache() function
Quoted 16 lines · On Tue, 8 Jan 2008 17:28:56 -0500 Rik van Riel <[email protected]> wrote:
Quoted 5 lines · On Tue, 8 Jan 2008 14:18:40 -0800 (PST) Christoph Lameter <[email protected]>…
Quoted 2 lines · Rik van Riel
Define
page_file_cache()function to answer the question:
is page backed by a file?Quoted 7 lines
include/linux/mm_inline.h line 16
Quoted 4 lines
include/linux/mm_inline.h +4
-0+static inline int page_file_cache (struct page *page) +{ +if (PageSwapBacked (page)) +return 0 ;Could we call this PageNotFileBacked or so? PageSwapBacked is true for pages that are RAM based. Its a bit confusing.
Quoted 4 lines
PageNotFileBacked confuses me a little, since shared memory segments live in tmpfs and are kinda sorta file backed, but go to swap instead of to a filesystem when there is memory pressure.
How about PageIsNotCache() ? :)
When a page is a cache, there is an original data somewhere and can be dropped out.
Thanks,
-Kame
PATCH 4/19 Use an indexed array for LRU variables
In reply to Rik van RielV1 -> V2 [lts]:
+ Remove extraneous __dec_zone_state(zone, NR_ACTIVE) pointed out by Mel G.
Quoted 1 line
From [email protected] Wed Aug 29 11:39:51 2007
Currently we are defining explicit variables for the inactive and active list. An indexed array can be more generic and avoid repeating similar code in several places in the reclaim code.
We are saving a few bytes in terms of code size:
Before:
text data bss dec hex filename
4097753 573120 4092484 8763357 85b7dd vmlinux
After:
text data bss dec hex filename
4097729 573120 4092484 8763333 85b7c5 vmlinux
Having an easy way to add new lru lists may ease future work on the reclaim code.
include/linux/mm_inline.h | 34 ++++++++--- include/linux/mmzone.h | 17 +++-- mm/page_alloc.c | 9 +-- mm/swap.c | 2 mm/vmscan.c | 132 ++++++++++++++++++++++------------------------ mm/vmstat.c | 3 - 6 files changed, 107 insertions(+), 90 deletions(-)
include/linux/mmzone.h +11 -6
@@ -80,8 +80,8 @@ struct zone_padding {enum zone_stat_item {/* First 128 byte cacheline (assuming 64 bit words) */ NR_FREE_PAGES , -NR_INACTIVE , -NR_ACTIVE , +NR_INACTIVE ,/* must match order of LRU_[IN]ACTIVE */ +NR_ACTIVE ,/* " " " " " */ NR_ANON_PAGES ,/* Mapped anonymous pages */ NR_FILE_MAPPED ,/* pagecache pages mapped into pagetables. only modified from process context */
@@ -105,6 +105,13 @@ enum zone_stat_item {#endif NR_VM_ZONE_STAT_ITEMS }; +enum lru_list { +LRU_INACTIVE ,/* must match order of NR_[IN]ACTIVE */ +LRU_ACTIVE ,/* " " " " " */ +NR_LRU_LISTS }; + +#define for_each_lru (l) for (l = 0; l < NR_LRU_LISTS; l++) +struct per_cpu_pages {int count;/* number of pages in the list */ int high;/* high watermark, emptying needed */
@@ -258,10 +265,8 @@ struct zone {/* Fields commonly accessed by the page reclaim scanner */ spinlock_t lru_lock; -struct list_head active_list; -struct list_head inactive_list; -unsigned long nr_scan_active; -unsigned long nr_scan_inactive; +struct list_head list[NR_LRU_LISTS ]; +unsigned long nr_scan[NR_LRU_LISTS ];unsigned long pages_scanned;/* since last reclaim */ unsigned long flags;/* zone flags, see below */
include/linux/mm_inline.h +23 -11
@@ -30,43 +30,55 @@ static inline int page_file_cache(struct }static inline void +add_page_to_lru_list (struct zone *zone,struct page *page,enum lru_list l) +{ +list_add (&page->lru, &zone->list[l]); +__inc_zone_state (zone,NR_INACTIVE + l); +} + +static inline void +del_page_from_lru_list (struct zone *zone,struct page *page,enum lru_list l) +{ +list_del (&page->lru); +__dec_zone_state (zone,NR_INACTIVE + l); +} + + +static inline void add_page_to_active_list (struct zone *zone,struct page *page) { -list_add (&page->lru, &zone->active_list); -__inc_zone_state (zone,NR_ACTIVE ); +add_page_to_lru_list (zone, page,LRU_ACTIVE ); }static inline void add_page_to_inactive_list (struct zone *zone,struct page *page) { -list_add (&page->lru, &zone->inactive_list); -__inc_zone_state (zone,NR_INACTIVE ); +add_page_to_lru_list (zone, page,LRU_INACTIVE ); }static inline void del_page_from_active_list (struct zone *zone,struct page *page) { -list_del (&page->lru); -__dec_zone_state (zone,NR_ACTIVE ); +del_page_from_lru_list (zone, page,LRU_ACTIVE ); }static inline void del_page_from_inactive_list (struct zone *zone,struct page *page) { -list_del (&page->lru); -__dec_zone_state (zone,NR_INACTIVE ); +del_page_from_lru_list (zone, page,LRU_INACTIVE ); }static inline void del_page_from_lru (struct zone *zone,struct page *page) { +enum lru_list l =LRU_INACTIVE ; +list_del (&page->lru);if (PageActive (page)) {__ClearPageActive (page); -__dec_zone_state (zone,NR_ACTIVE ); - }else { -__dec_zone_state (zone,NR_INACTIVE ); + l =LRU_ACTIVE ; } +__dec_zone_state (zone,NR_INACTIVE + l); }#endif
mm/page_alloc.c +5 -4
@@ -3413,6 +3413,7 @@ static void __meminit free_area_init_corfor (j =0 ; j <MAX_NR_ZONES ; j++) {struct zone *zone = pgdat->node_zones + j;unsigned long size, realsize, memmap_pages; +enum lru_list l; size =zone_spanned_pages_in_node (nid, j, zones_size); realsize = size - zone_absent_pages_in_node(nid, j,
@@ -3462,10 +3463,10 @@ static void __meminit free_area_init_cor zone->prev_priority =DEF_PRIORITY ;zone_pcp_init (zone); -INIT_LIST_HEAD (&zone->active_list); -INIT_LIST_HEAD (&zone->inactive_list); - zone->nr_scan_active =0 ; - zone->nr_scan_inactive =0 ; +for_each_lru (l) { +INIT_LIST_HEAD (&zone->list[l]); + zone->nr_scan[l] =0 ; + }zap_zone_vm_stats (zone); zone->flags =0 ;if (!size)
mm/swap.c +1 -1
@@ -118,7 +118,7 @@ static void pagevec_move_tail(struct pagspin_lock (&zone->lru_lock); }if (PageLRU (page) && !PageActive (page)) { -list_move_tail (&page->lru, &zone->inactive_list); +list_move_tail (&page->lru, &zone->list[LRU_INACTIVE ]); pgmoved++; } }
mm/vmscan.c +67 -70
238 lines not on this page · raw message
mm/vmstat.c +2 -1
@@ -758,7 +758,8 @@ static void zoneinfo_show_print(struct s zone->pages_low, zone->pages_high, zone->pages_scanned, - zone->nr_scan_active, zone->nr_scan_inactive, + zone->nr_scan[LRU_ACTIVE ], + zone->nr_scan[LRU_INACTIVE ], zone->spanned_pages, zone->present_pages);
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 5/19 split LRU lists into anon & file sets
In reply to Rik van RielSplit the LRU lists in two, one set for pages that are backed by real file systems ("file") and one for pages that are backed by memory and swap ("anon"). The latter includes tmpfs.
Eventually mlocked pages will be taken off the LRUs alltogether. A patch for that already exists and just needs to be integrated into this series.
This patch mostly has the infrastructure and a basic policy to balance how much we scan the anon lists and how much we scan the file lists. The big policy changes are in separate patches.
fs/proc/proc_misc.c +35 -31
@@ -153,43 +153,47 @@ static int meminfo_read_proc(char *page,* Tagged format, for easy grepping and expansion. */ len = sprintf(page, - "MemTotal: %8lu kB\n" - "MemFree: %8lu kB\n" - "Buffers: %8lu kB\n" - "Cached: %8lu kB\n" - "SwapCached: %8lu kB\n" - "Active: %8lu kB\n" - "Inactive: %8lu kB\n" + "MemTotal: %8lu kB\n" + "MemFree: %8lu kB\n" + "Buffers: %8lu kB\n" + "Cached: %8lu kB\n" + "SwapCached: %8lu kB\n" + "Active(anon): %8lu kB\n" + "Inactive(anon): %8lu kB\n" + "Active(file): %8lu kB\n" + "Inactive(file): %8lu kB\n" #ifdef CONFIG_HIGHMEM - "HighTotal: %8lu kB\n" - "HighFree: %8lu kB\n" - "LowTotal: %8lu kB\n" - "LowFree: %8lu kB\n" -#endif - "SwapTotal: %8lu kB\n" - "SwapFree: %8lu kB\n" - "Dirty: %8lu kB\n" - "Writeback: %8lu kB\n" - "AnonPages: %8lu kB\n" - "Mapped: %8lu kB\n" - "Slab: %8lu kB\n" - "SReclaimable: %8lu kB\n" - "SUnreclaim: %8lu kB\n" - "PageTables: %8lu kB\n" - "NFS_Unstable: %8lu kB\n" - "Bounce: %8lu kB\n" - "CommitLimit: %8lu kB\n" - "Committed_AS: %8lu kB\n" - "VmallocTotal: %8lu kB\n" - "VmallocUsed: %8lu kB\n" - "VmallocChunk: %8lu kB\n", + "HighTotal: %8lu kB\n" + "HighFree: %8lu kB\n" + "LowTotal: %8lu kB\n" + "LowFree: %8lu kB\n" +#endif + "SwapTotal: %8lu kB\n" + "SwapFree: %8lu kB\n" + "Dirty: %8lu kB\n" + "Writeback: %8lu kB\n" + "AnonPages: %8lu kB\n" + "Mapped: %8lu kB\n" + "Slab: %8lu kB\n" + "SReclaimable: %8lu kB\n" + "SUnreclaim: %8lu kB\n" + "PageTables: %8lu kB\n" + "NFS_Unstable: %8lu kB\n" + "Bounce: %8lu kB\n" + "CommitLimit: %8lu kB\n" + "Committed_AS: %8lu kB\n" + "VmallocTotal: %8lu kB\n" + "VmallocUsed: %8lu kB\n" + "VmallocChunk: %8lu kB\n", K(i.totalram), K(i.freeram), K(i.bufferram), K(cached), K(total_swapcache_pages), - K(global_page_state(NR_ACTIVE)), - K(global_page_state(NR_INACTIVE)), + K(global_page_state(NR_ACTIVE_ANON)), + K(global_page_state(NR_INACTIVE_ANON)), + K(global_page_state(NR_ACTIVE_FILE)), + K(global_page_state(NR_INACTIVE_FILE)), #ifdef CONFIG_HIGHMEM K(i.totalhigh), K(i.freehigh),
fs/cifs/file.c +2 -2
@@ -1783,7 +1783,7 @@ static void cifs_copy_cache_pages(structSetPageUptodate (page);unlock_page (page);if (!pagevec_add (plru_pvec, page)) -__pagevec_lru_add (plru_pvec); +__pagevec_lru_add_file (plru_pvec); data +=PAGE_CACHE_SIZE ; }return ;
@@ -1921,7 +1921,7 @@ static int cifs_readpages(struct file *f bytes_read =0 ; } -pagevec_lru_add (&lru_pvec); +pagevec_lru_add_file (&lru_pvec);/* need to free smb_read_data buf before exit */ if (smb_read_data) {
fs/ntfs/file.c +2 -2
@@ -439,7 +439,7 @@ static inline int __ntfs_grab_cache_page pages[nr] = *cached_page;page_cache_get (*cached_page);if (unlikely (!pagevec_add (lru_pvec, *cached_page))) -__pagevec_lru_add (lru_pvec); +__pagevec_lru_add_file (lru_pvec); *cached_page =NULL ; } index++;
@@ -2084,7 +2084,7 @@ err_out: OSYNC_METADATA|OSYNC_DATA); } } -pagevec_lru_add (&lru_pvec); +pagevec_lru_add_file (&lru_pvec);ntfs_debug ("Done. Returning %s (written 0x%lx, status %li)." , written ?"written" :"status" , (unsigned long )written, (long )status);
fs/nfs/dir.c +1 -1
@@ -1497,7 +1497,7 @@ static int nfs_symlink(struct inode *dirif (!add_to_page_cache (page, dentry->d_inode->i_mapping,0 ,GFP_KERNEL )) {pagevec_add (&lru_pvec, page); -pagevec_lru_add (&lru_pvec); +pagevec_lru_add_file (&lru_pvec);SetPageUptodate (page);unlock_page (page); }else
fs/ramfs/file-nommu.c +2 -2
@@ -111,12 +111,12 @@ static int ramfs_nommu_expand_for_mappin goto add_error;if (!pagevec_add (&lru_pvec, page)) -__pagevec_lru_add (&lru_pvec); +__pagevec_lru_add_file (&lru_pvec);unlock_page (page); } -pagevec_lru_add (&lru_pvec); +pagevec_lru_add_file (&lru_pvec);return 0 ; fsize_exceeded:
drivers/base/node.c +26 -22
59 lines not on this page · raw message
mm/memory.c +3 -3
@@ -1665,7 +1665,7 @@ gotten:set_pte_at (mm, address, page_table, entry);update_mmu_cache (vma, address, entry);SetPageSwapBacked (new_page); -lru_cache_add_active (new_page); +lru_cache_add_active_anon (new_page);page_add_new_anon_rmap (new_page, vma, address);/* Free the old page.. */
@@ -2133,7 +2133,7 @@ static int do_anonymous_page(struct mm_s goto release;inc_mm_counter (mm, anon_rss);SetPageSwapBacked (page); -lru_cache_add_active (page); +lru_cache_add_active_anon (page);page_add_new_anon_rmap (page, vma, address);set_pte_at (mm, address, page_table, entry);
@@ -2287,7 +2287,7 @@ static int __do_fault(struct mm_struct *if (anon) {inc_mm_counter (mm, anon_rss);SetPageSwapBacked (page); -lru_cache_add_active (page); +lru_cache_add_active_anon (page);page_add_new_anon_rmap (page, vma, address); }else {inc_mm_counter (mm, file_rss);
mm/page_alloc.c +17 -7
@@ -1889,10 +1889,13 @@ void show_free_areas(void) } } - printk("Active:%lu inactive:%lu dirty:%lu writeback:%lu unstable:%lu\n" + printk("Active_anon:%lu active_file:%lu inactive_anon%lu\n" + " inactive_file:%lu dirty:%lu writeback:%lu unstable:%lu\n" " free:%lu slab:%lu mapped:%lu pagetables:%lu bounce:%lu\n", - global_page_state(NR_ACTIVE), - global_page_state(NR_INACTIVE), + global_page_state(NR_ACTIVE_ANON), + global_page_state(NR_ACTIVE_FILE), + global_page_state(NR_INACTIVE_ANON), + global_page_state(NR_INACTIVE_FILE), global_page_state(NR_FILE_DIRTY), global_page_state(NR_WRITEBACK), global_page_state(NR_UNSTABLE_NFS),
@@ -1915,8 +1918,10 @@ void show_free_areas(void)" min:%lukB" " low:%lukB" " high:%lukB" -" active:%lukB" -" inactive:%lukB" +" active_anon:%lukB" +" inactive_anon:%lukB" +" active_file:%lukB" +" inactive_file:%lukB" " present:%lukB" " pages_scanned:%lu" " all_unreclaimable? %s"
@@ -1926,8 +1931,10 @@ void show_free_areas(void)K (zone->pages_min),K (zone->pages_low),K (zone->pages_high), -K (zone_page_state (zone,NR_ACTIVE )), -K (zone_page_state (zone,NR_INACTIVE )), +K (zone_page_state (zone,NR_ACTIVE_ANON )), +K (zone_page_state (zone,NR_INACTIVE_ANON )), +K (zone_page_state (zone,NR_ACTIVE_FILE )), +K (zone_page_state (zone,NR_INACTIVE_FILE )),K (zone->present_pages), zone->pages_scanned, (zone_is_all_unreclaimable (zone) ?"yes" :"no" )
@@ -3467,6 +3474,9 @@ static void __meminit free_area_init_corINIT_LIST_HEAD (&zone->list[l]); zone->nr_scan[l] =0 ; } + zone->recent_rotated_anon =0 ; + zone->recent_rotated_file =0 ; +//TODO recent_scanned_* ??? zap_zone_vm_stats (zone); zone->flags =0 ;if (!size)
mm/swap.c +113 -22
204 lines not on this page · raw message
mm/migrate.c +8 -2
@@ -60,9 +60,15 @@ static inline void move_to_lru(struct pa* the PG_active bit is off. */ ClearPageActive (page); -lru_cache_add_active (page); +if (page_file_cache (page)) +lru_cache_add_active_file (page); +else +lru_cache_add_active_anon (page); }else { -lru_cache_add (page); +if (page_file_cache (page)) +lru_cache_add_file (page); +else +lru_cache_add_anon (page); }put_page (page); }
mm/readahead.c +1 -1
@@ -229,7 +229,7 @@ int do_page_cache_readahead(struct addre*/ unsigned long max_sane_readahead (unsigned long nr) { -return min (nr, (node_page_state (numa_node_id (),NR_INACTIVE ) +return min (nr, (node_page_state (numa_node_id (),NR_INACTIVE_FILE ) +node_page_state (numa_node_id (),NR_FREE_PAGES )) /2 ); }
mm/filemap.c +7 -2
@@ -34,6 +34,7 @@#include <linux/cpuset.h> #include <linux/hardirq.h> /* for BUG_ON(!in_atomic()) only */ #include <linux/memcontrol.h> +#include <linux/mm_inline.h> /* for page_file_cache() */ #include "internal.h" /*
@@ -493,8 +494,12 @@ int add_to_page_cache_lru(struct page *p pgoff_t offset, gfp_t gfp_mask) { int ret = add_to_page_cache(page, mapping, offset, gfp_mask); -if (ret ==0 ) -lru_cache_add (page); +if (ret ==0 ) { +if (page_file_cache (page)) +lru_cache_add_file (page); +else +lru_cache_add_active_anon (page); + }return ret; }
mm/vmstat.c +9 -5
@@ -686,8 +686,10 @@ const struct seq_operations pagetypeinfostatic const char *const vmstat_text[] = {/* Zoned VM counters */ "nr_free_pages" , -"nr_inactive" , -"nr_active" , +"nr_inactive_anon" , +"nr_active_anon" , +"nr_inactive_file" , +"nr_active_file" ,"nr_anon_pages" ,"nr_mapped" ,"nr_file_pages" ,
@@ -750,7 +752,7 @@ static void zoneinfo_show_print(struct s"\n min %lu" "\n low %lu" "\n high %lu" -"\n scanned %lu (a: %lu i: %lu)" +"\n scanned %lu (aa: %lu ia: %lu af: %lu if: %lu)" "\n spanned %lu" "\n present %lu" , zone_page_state(zone, NR_FREE_PAGES),
@@ -758,8 +760,10 @@ static void zoneinfo_show_print(struct s zone->pages_low, zone->pages_high, zone->pages_scanned, - zone->nr_scan[LRU_ACTIVE ], - zone->nr_scan[LRU_INACTIVE ], + zone->nr_scan[LRU_ACTIVE_ANON ], + zone->nr_scan[LRU_INACTIVE_ANON ], + zone->nr_scan[LRU_ACTIVE_FILE ], + zone->nr_scan[LRU_INACTIVE_FILE ], zone->spanned_pages, zone->present_pages);
mm/vmscan.c +214 -239
760 lines not on this page · raw message
mm/swap_state.c +1 -1
@@ -300,7 +300,7 @@ struct page *read_swap_cache_async(swp_e/* * Initiate read into locked page and return. */ -lru_cache_add_active (new_page); +lru_cache_add_active_anon (new_page);swap_readpage (NULL , new_page);return new_page; }
include/linux/mmzone.h +30 -5
@@ -80,21 +80,23 @@ struct zone_padding {enum zone_stat_item {/* First 128 byte cacheline (assuming 64 bit words) */ NR_FREE_PAGES , -NR_INACTIVE ,/* must match order of LRU_[IN]ACTIVE */ -NR_ACTIVE ,/* " " " " " */ +NR_INACTIVE_ANON ,/* must match order of LRU_[IN]ACTIVE_* */ +NR_ACTIVE_ANON ,/* " " " " " */ +NR_INACTIVE_FILE ,/* " " " " " */ +NR_ACTIVE_FILE ,/* " " " " " */ NR_ANON_PAGES ,/* Mapped anonymous pages */ NR_FILE_MAPPED ,/* pagecache pages mapped into pagetables. only modified from process context */ NR_FILE_PAGES ,NR_FILE_DIRTY ,NR_WRITEBACK , -/* Second 128 byte cacheline */ NR_SLAB_RECLAIMABLE ,NR_SLAB_UNRECLAIMABLE ,NR_PAGETABLE ,/* used for pagetables */ NR_UNSTABLE_NFS ,/* NFS unstable pages */ NR_BOUNCE ,NR_VMSCAN_WRITE , +/* Second 128 byte cacheline */ #ifdef CONFIG_NUMA NUMA_HIT ,/* allocated in intended node */ NUMA_MISS ,/* allocated in non intended node */
@@ -105,13 +107,32 @@ enum zone_stat_item {#endif NR_VM_ZONE_STAT_ITEMS }; +/* +* We do arithmetic on the LRU lists in various places in the code, +* so it is important to keep the active lists LRU_ACTIVE higher in +* the array than the corresponding inactive lists, and to keep +* the *_FILE lists LRU_FILE higher than the corresponding _ANON lists. +*/ +#define LRU_BASE 0 +#define LRU_ANON LRU_BASE +#define LRU_ACTIVE 1 +#define LRU_FILE 2 +enum lru_list { -LRU_INACTIVE ,/* must match order of NR_[IN]ACTIVE */ -LRU_ACTIVE ,/* " " " " " */ +LRU_INACTIVE_ANON =LRU_BASE , +LRU_ACTIVE_ANON =LRU_BASE +LRU_ACTIVE , +LRU_INACTIVE_FILE =LRU_BASE +LRU_FILE , +LRU_ACTIVE_FILE =LRU_BASE +LRU_FILE +LRU_ACTIVE ,NR_LRU_LISTS };#define for_each_lru (l) for (l = 0; l < NR_LRU_LISTS; l++) +static inline int is_file_lru (enum lru_list l) +{ +BUILD_BUG_ON (LRU_INACTIVE_FILE !=2 ||LRU_ACTIVE_FILE !=3 ); +return (l/2 ==1 ); +} +struct per_cpu_pages {int count;/* number of pages in the list */ int high;/* high watermark, emptying needed */
@@ -267,6 +288,10 @@ struct zone {spinlock_t lru_lock;struct list_head list[NR_LRU_LISTS ];unsigned long nr_scan[NR_LRU_LISTS ]; + +unsigned long recent_rotated_anon; +unsigned long recent_rotated_file; +unsigned long pages_scanned;/* since last reclaim */ unsigned long flags;/* zone flags, see below */
include/linux/mm_inline.h +39 -14
98 lines not on this page · raw message
include/linux/pagevec.h +12 -4
@@ -23,8 +23,10 @@ struct pagevec {void __pagevec_release (struct pagevec *pvec);void __pagevec_release_nonlru (struct pagevec *pvec);void __pagevec_free (struct pagevec *pvec); -void __pagevec_lru_add (struct pagevec *pvec); -void __pagevec_lru_add_active (struct pagevec *pvec); +void __pagevec_lru_add_file (struct pagevec *pvec); +void __pagevec_lru_add_active_file (struct pagevec *pvec); +void __pagevec_lru_add_anon (struct pagevec *pvec); +void __pagevec_lru_add_active_anon (struct pagevec *pvec);void pagevec_strip (struct pagevec *pvec);void pagevec_swap_free (struct pagevec *pvec); unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
@@ -82,10 +84,16 @@ static inline void pagevec_free(struct p __pagevec_free(pvec); } -static inline void pagevec_lru_add (struct pagevec *pvec) +static inline void pagevec_lru_add_file (struct pagevec *pvec) {if (pagevec_count (pvec)) -__pagevec_lru_add (pvec); +__pagevec_lru_add_file (pvec); +} + +static inline void pagevec_lru_add_anon (struct pagevec *pvec) +{ +if (pagevec_count (pvec)) +__pagevec_lru_add_anon (pvec); }#endif /* _LINUX_PAGEVEC_H */
include/linux/vmstat.h +10 -0
@@ -149,6 +149,16 @@ static inline unsigned long zone_page_streturn x; } +extern unsigned long global_lru_pages (void ); + +static inline unsigned long zone_lru_pages (struct zone *zone) +{ +return (zone_page_state (zone,NR_ACTIVE_ANON ) + +zone_page_state (zone,NR_ACTIVE_FILE ) + +zone_page_state (zone,NR_INACTIVE_ANON ) + +zone_page_state (zone,NR_INACTIVE_FILE )); +} +#ifdef CONFIG_NUMA /* * Determine the per node value of a stat item. This function
mm/page-writeback.c +2 -6
@@ -270,9 +270,7 @@ static unsigned long highmem_dirtyable_mstruct zone *z = &NODE_DATA (node)->node_zones[ZONE_HIGHMEM ]; - x +=zone_page_state (z,NR_FREE_PAGES ) - +zone_page_state (z,NR_INACTIVE ) - +zone_page_state (z,NR_ACTIVE ); + x +=zone_page_state (z,NR_FREE_PAGES ) +zone_lru_pages (z); }/* * Make sure that the number of highmem pages is never larger
@@ -290,9 +288,7 @@ static unsigned long determine_dirtyable {unsigned long x; - x =global_page_state (NR_FREE_PAGES ) - +global_page_state (NR_INACTIVE ) - +global_page_state (NR_ACTIVE ); + x =global_page_state (NR_FREE_PAGES ) +global_lru_pages ();if (!vm_highmem_is_dirtyable) x -=highmem_dirtyable_memory (x);
include/linux/swap.h +5 -3
@@ -171,8 +171,10 @@ extern unsigned int nr_free_pagecache_pa/* linux/mm/swap.c */ -extern void FASTCALL (lru_cache_add (struct page *)); -extern void FASTCALL (lru_cache_add_active (struct page *)); +extern void FASTCALL (lru_cache_add_file (struct page *)); +extern void FASTCALL (lru_cache_add_anon (struct page *)); +extern void FASTCALL (lru_cache_add_active_file (struct page *)); +extern void FASTCALL (lru_cache_add_active_anon (struct page *));extern void FASTCALL (activate_page (struct page *));extern void FASTCALL (mark_page_accessed (struct page *));extern void lru_add_drain (void );
@@ -185,7 +187,7 @@ extern unsigned long try_to_free_pages(s gfp_t gfp_mask);extern unsigned long try_to_free_mem_cgroup_pages (struct mem_cgroup *mem,gfp_t gfp_mask); -extern int __isolate_lru_page (struct page *page,int mode); +extern int __isolate_lru_page (struct page *page,int mode,int file);extern unsigned long shrink_all_memory (unsigned long nr_pages);extern int vm_swappiness;extern int remove_mapping (struct address_space *mapping,struct page *page);
include/linux/memcontrol.h +6 -13
@@ -42,7 +42,7 @@ extern unsigned long mem_cgroup_isolate_ unsigned long *scanned, int order, int mode, struct zone *z, struct mem_cgroup *mem_cont, - int active); + int active, int file);extern void mem_cgroup_out_of_memory (struct mem_cgroup *mem,gfp_t gfp_mask);extern int mem_cgroup_cache_charge (struct page *page,struct mm_struct *mm,gfp_t gfp_mask);
@@ -69,10 +69,8 @@ extern void mem_cgroup_note_reclaim_prioextern void mem_cgroup_record_reclaim_priority (struct mem_cgroup *mem,int priority); -extern long mem_cgroup_calc_reclaim_active (struct mem_cgroup *mem, -struct zone *zone,int priority); -extern long mem_cgroup_calc_reclaim_inactive (struct mem_cgroup *mem, -struct zone *zone,int priority); +extern long mem_cgroup_calc_reclaim (struct mem_cgroup *mem,struct zone *zone, +int priority,enum lru_list lru);#else /* CONFIG_CGROUP_MEM_CONT */ static inline void mm_init_cgroup(struct mm_struct *mm,
@@ -170,14 +168,9 @@ static inline void mem_cgroup_record_rec { } -static inline long mem_cgroup_calc_reclaim_active (struct mem_cgroup *mem, -struct zone *zone,int priority) -{ -return 0 ; -} - -static inline long mem_cgroup_calc_reclaim_inactive (struct mem_cgroup *mem, -struct zone *zone,int priority) +static inline long mem_cgroup_calc_reclaim (struct mem_cgroup *mem, +struct zone *zone,int priority, +int active,int file) {return 0 ; }
mm/memcontrol.c +74 -92
310 lines not on this page · raw message
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
It may be good to coordinate this with Andrea Arcangeli's OOM fixes.
Also would it be possible to create generic functions that can move pages in pagevecs to an arbitrary lru list?
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 1 line · On Tue, 8 Jan 2008 14:22:38 -0800 (PST) Christoph Lameter <[email protected]>…
It may be good to coordinate this with Andrea Arcangeli's OOM fixes.
Probably. With the split LRU lists (and the noreclaim LRUs), we can simplify the OOM test a lot:
If free + file_active + file_inactive <= zone->pages_high and swap space is full, the system is doomed. No need for guesswork.
Quoted 2 lines
Also would it be possible to create generic functions that can move pages in pagevecs to an arbitrary lru list?
What would you use those functions for?
Or am I simply misunderstanding your idea?
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 4 lines · Rik van Riel
Quoted 2 lines
Also would it be possible to create generic functions that can move pages in pagevecs to an arbitrary lru list?
What would you use those functions for?
We keep on duplicating the pagevec lru operation functions in mm/swap.c. Some generic stuff would reduce the code size.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 9 lines · On Tue, 8 Jan 2008 14:42:03 -0800 (PST) Christoph Lameter <[email protected]>…
Quoted 4 lines · Rik van Riel
Quoted 2 lines
Also would it be possible to create generic functions that can move pages in pagevecs to an arbitrary lru list?
What would you use those functions for?
We keep on duplicating the pagevec lru operation functions in
mm/swap.c. Some generic stuff would reduce the code size.
Good idea. Added to my TODO list :)
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
In reply to Rik van RielI like this patch set thank you.
Quoted 4 lines · On Tue, 08 Jan 2008 15:59:44 -0500 Rik van Riel <[email protected]> wrote:
Index:
linux-2.6.24-rc6-mm1/mm/memcontrol.c
===================================================================mm/memcontrol.c +0
-0
<snip>
Quoted 21 lines
mm/memcontrol.c +2
-10-enum mem_cgroup_zstat_index { -MEM_CGROUP_ZSTAT_ACTIVE , -MEM_CGROUP_ZSTAT_INACTIVE , - -NR_MEM_CGROUP_ZSTAT , -}; -struct mem_cgroup_per_zone {/* * spin_lock to protect the per cgroup LRU */ spinlock_t lru_lock; -struct list_head active_list; -struct list_head inactive_list; -unsigned long count[NR_MEM_CGROUP_ZSTAT ]; +struct list_head lists[NR_LRU_LISTS ]; +unsigned long count[NR_LRU_LISTS ]; };/* Macro for accessing counter */ #define MEM_CGROUP_ZSTAT (mz, idx) ((mz)->count[(idx)])
mm/memcontrol.c struct page_cgroup { · line 156
Quoted 5 lines
mm/memcontrol.c +1
-0@@ -160,6 +152,7 @@ struct page_cgroup { };#define PAGE_CGROUP_FLAG_CACHE (0x1)/* charged as cache */ #define PAGE_CGROUP_FLAG_ACTIVE (0x2)/* page is active in this cgroup */ +#define PAGE_CGROUP_FLAG_FILE (0x4)/* page is file system backed */
Now, we don't have control_type and a feature for accounting only CACHE. Balbir-san, do you have some new plan ?
BTW, is it better to use PageSwapBacked(pc->page) rather than adding a new flag PAGE_CGROUP_FLAG_FILE ?
PAGE_CGROUP_FLAG_ACTIVE is used because global reclaim can change ACTIVE/INACTIVE attribute without accessing memory cgroup. (Then, we cannot trust PageActive(pc->page))
ANON <-> FILE attribute can be changed dinamically (after added to LRU) ?
If no, using page_file_cache(pc->page) will be easy.
Thanks,
-Kame
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 31 lines · KAMEZAWA Hiroyuki
I like this patch set thank you.
Quoted 4 lines · On Tue, 08 Jan 2008 15:59:44 -0500 Rik van Riel <[email protected]> wrote:
Index:
linux-2.6.24-rc6-mm1/mm/memcontrol.c
===================================================================mm/memcontrol.c +0
-0<snip>
Quoted 21 lines
mm/memcontrol.c +2
-10-enum mem_cgroup_zstat_index { -MEM_CGROUP_ZSTAT_ACTIVE , -MEM_CGROUP_ZSTAT_INACTIVE , - -NR_MEM_CGROUP_ZSTAT , -}; -struct mem_cgroup_per_zone {/* * spin_lock to protect the per cgroup LRU */ spinlock_t lru_lock; -struct list_head active_list; -struct list_head inactive_list; -unsigned long count[NR_MEM_CGROUP_ZSTAT ]; +struct list_head lists[NR_LRU_LISTS ]; +unsigned long count[NR_LRU_LISTS ]; };/* Macro for accessing counter */ #define MEM_CGROUP_ZSTAT (mz, idx) ((mz)->count[(idx)])@@ -160,6 +152,7 @@ struct page_cgroup {
Quoted 9 lines
mm/memcontrol.c struct page_cgroup { · line 156
Quoted 5 lines
mm/memcontrol.c +1
-0};#define PAGE_CGROUP_FLAG_CACHE (0x1)/* charged as cache */ #define PAGE_CGROUP_FLAG_ACTIVE (0x2)/* page is active in this cgroup */ +#define PAGE_CGROUP_FLAG_FILE (0x4)/* page is file system backed */ Now, we don't have
control_typeand a feature for accounting only CACHE. Balbir-san, do you have some new plan ?
Hi, KAMEZAWA-San,
The control_type feature is gone. We still have cached page accounting, but we do not allow control of only RSS pages anymore. We need to control both RSS+cached pages. I do not understand your question about new plan? Is it about adding back control_type?
Quoted 8 lines
BTW, is it better to use
PageSwapBacked(pc->page)rather than adding a new flagPAGE_CGROUP_FLAG_FILE?
PAGE_CGROUP_FLAG_ACTIVEis used because global reclaim can change ACTIVE/INACTIVE attribute without accessing memory cgroup. (Then, we cannot trustPageActive(pc->page))
Yes, correct. A page active on the node's zone LRU need not be active in the memory cgroup.
Quoted 7 lines
ANON <-> FILE attribute can be changed dinamically (after added to LRU) ?
If no, using
page_file_cache(pc->page)will be easy.Thanks,
-Kame
Signature · 10 lines
Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 9 lines · On Thu, 10 Jan 2008 07:51:33 +0530 Balbir Singh <[email protected]>…
Quoted 8 lines
Quoted 4 lines
#define
PAGE_CGROUP_FLAG_CACHE(0x1) /* charged as cache */
#definePAGE_CGROUP_FLAG_ACTIVE(0x2) /* page is active in this cgroup */
+#definePAGE_CGROUP_FLAG_FILE(0x4) /* page is file system backed */Now, we don't have
control_typeand a feature for accounting only CACHE. Balbir-san, do you have some new plan ?
Quoted 7 lines
Hi, KAMEZAWA-San,
The
control_typefeature is gone. We still have cached page accounting, but we do not allow control of only RSS pages anymore. We need to control both RSS+cached pages. I do not understand your question about new plan? Is it about adding backcontrol_type?
Ah, just wanted to confirm that we can drop PAGE_CGROUP_FLAG_CACHE if page_file_cache() function and split-LRU is introduced.
Thanks you.
-Kame
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 14 lines · KAMEZAWA Hiroyuki
Quoted 11 lines · On Thu, 10 Jan 2008 07:51:33 +0530 Balbir Singh <[email protected]>…
Quoted 8 lines
Quoted 4 lines
#define
PAGE_CGROUP_FLAG_CACHE(0x1) /* charged as cache */
#definePAGE_CGROUP_FLAG_ACTIVE(0x2) /* page is active in this cgroup */
+#definePAGE_CGROUP_FLAG_FILE(0x4) /* page is file system backed */Now, we don't have
control_typeand a feature for accounting only CACHE. Balbir-san, do you have some new plan ?Hi, KAMEZAWA-San,
Quoted 8 lines
Quoted 5 lines
The
control_typefeature is gone. We still have cached page accounting, but we do not allow control of only RSS pages anymore. We need to control both RSS+cached pages. I do not understand your question about new plan? Is it about adding backcontrol_type?Ah, just wanted to confirm that we can drop
PAGE_CGROUP_FLAG_CACHEifpage_file_cache()function and split-LRU is introduced.
Earlier we would have had a problem, since we even accounted for swap cache with PAGE_CGROUP_FLAG_CACHE and I think page_file_cache() does not account swap cache pages with page_file_cache(). Our accounting is based on mapped vs unmapped whereas the new code from Rik accounts file vs anonymous. I suspect we could live a little while longer with PAGE_CGROUP_FLAG_CACHE and then if we do not need it at all, we can mark it down for removal. What do you think?
Signature · 10 lines
Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 9 lines · On Thu, 10 Jan 2008 08:56:31 +0530 Balbir Singh <[email protected]>…
Quoted 8 lines
Quoted 5 lines
The
control_typefeature is gone. We still have cached page accounting, but we do not allow control of only RSS pages anymore. We need to control both RSS+cached pages. I do not understand your question about new plan? Is it about adding backcontrol_type?Ah, just wanted to confirm that we can drop
PAGE_CGROUP_FLAG_CACHEifpage_file_cache()function and split-LRU is introduced.
Quoted 7 lines
Earlier we would have had a problem, since we even accounted for swap cache with
PAGE_CGROUP_FLAG_CACHEand I thinkpage_file_cache()does not account swap cache pages withpage_file_cache(). Our accounting is based on mapped vs unmapped whereas the new code from Rik accounts file vs anonymous. I suspect we could live a little while longer withPAGE_CGROUP_FLAG_CACHEand then if we do not need it at all, we can mark it down for removal. What do you think?
Okay, I have no objection.
Thanks,
-Kame
Re: [patch 05/19] split LRU lists into anon & file sets
In reply to Rik van RielQuoted 21 lines · On Tue, 08 Jan 2008 15:59:44 -0500 Rik van Riel <[email protected]> wrote:
mm/vmscan.c +21
-0+ rotate_sum = zone->recent_rotated_file + zone->recent_rotated_anon; + +/* Keep a floating average of RECENT references. */ +if (unlikely (rotate_sum >min (anon, file))) { +spin_lock_irq (&zone->lru_lock); + zone->recent_rotated_file /=2 ; + zone->recent_rotated_anon /=2 ; +spin_unlock_irq (&zone->lru_lock); + rotate_sum /=2 ; + } + +/* +* With swappiness at 100, anonymous and file have the same priority. +* This scanning priority is essentially the inverse of IO cost. +*/ + anon_prio = sc->swappiness; + file_prio =200 - sc->swappiness; + +/* +* anon recent_rotated_anon +* %anon = 100 * ----------- / ------------------- * IO cost
mm/vmscan.c static void shrink_active_list(unsigned · line 1208
Quoted 10 lines
mm/vmscan.c +10
-0+* anon + file rotate_sum +*/ + ap = (anon_prio * anon) / (anon + file +1 ); + ap *= rotate_sum / (zone->recent_rotated_anon +1 ); +if (ap ==0 ) + ap =1 ; +else if (ap >100 ) + ap =100 ; + percent[0 ] = ap; +
Hmm, it seems..
When a program copies large amount of files, recent_rotated_file increases rapidly and
rotate_sum
----------recent_rotated_anon
will be very big.
And %ap will be big regardless of vm_swappiness if it's not 0.
I think # of recent_successful_pageout(anon/file) should be took into account...
I'm sorry if I miss something.
Thanks,
-Kame
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 9 lines · On Thu, 10 Jan 2008 11:28:49 +0900 KAMEZAWA Hiroyuki…
Hmm, it seems..
When a program copies large amount of files,
recent_rotated_fileincreases rapidly androtate_sum ----------
recent_rotated_anon
Quoted 7 lines
will be very big.
And %ap will be big regardless of
vm_swappinessif it's not 0.I think # of
recent_successful_pageout(anon/file)should be took into account...I'm sorry if I miss something.
You are right. I wonder if this, again, is a case of myself or Lee forward porting old code. I remember having (had) a very different version of get_scan_ratio() at some point in the past, but I cannot remember if we discarded this version for that other version, or the other way around :(
Lee, would you by any chance still have some alternative versions of get_scan_ratio() around? I'm searching through my systems, but have not found it yet...
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
In reply to Rik van RielHi Rik
Review
Quoted 8 lines
(quoted diff) +3
-2-static inline long mem_cgroup_calc_reclaim_inactive(struct mem_cgroup *mem, - struct zone *zone, int priority) +static inline long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, + struct zone *zone, int priority, + int active, int file) { return 0; }
it can't compile if memcgroup turn off.
because current mem_cgroup_calc_reclaim type is below.
long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, struct zone *zone,
int priority, enum lru_list lru)
after patched below, it can compile.
I hope you don't think unpleasant by a trivial point out.
regard.
- kosaki
include/linux/memcontrol.h 2008-01-11 12:08:29.000000000 +0900 renamed from include/linux/memcontrol.h 2008-01-11 11:10:16.000000000 +0900 +2 -3
@@ -168,9 +168,8 @@ { } -static inline long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, - struct zone *zone, int priority, - int active, int file) +static inline long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, struct zone *zone, + int priority, enum lru_list lru) { return 0; }
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 12 lines · On Fri, 11 Jan 2008 12:59:31 +0900 KOSAKI Motohiro…
Hi Rik
Review
Quoted 8 lines
(quoted diff) +3
-2-static inline long mem_cgroup_calc_reclaim_inactive(struct mem_cgroup *mem, - struct zone *zone, int priority) +static inline long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, + struct zone *zone, int priority, + int active, int file) { return 0; }it can't compile if memcgroup turn off.
Doh! Good point.
Thank you for pointing out this error. I applied your fix to my tree, it will be in the next version.
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
In reply to Rik van RielHi Rik
Review
Quoted 5 lines
(quoted diff) +5
-0+static inline int is_file_lru(enum lru_list l) +{ + BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3); + return (l/2 == 1); +}
below patch is a bit cleanup proposal.
i think LRU_FILE is more clarify than "/2".
What do you think it?
include/linux/mmzone.h 2008-01-11 14:40:31.000000000 +0900 renamed from include/linux/mmzone.h 2008-01-11 11:10:30.000000000 +0900 +1 -1
@@ -147,7 +147,7 @@ static inline int is_file_lru(enum lru_list l) { BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3); - return (l/2 == 1); + return !!(l & LRU_FILE); } struct per_cpu_pages {
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 4 lines · On Fri, 11 Jan 2008 15:24:34 +0900 KOSAKI Motohiro…
below patch is a bit cleanup proposal.
i thinkLRU_FILEis more clarify than "/2".What do you think it?
Thank you for the cleanup, your version looks a lot nicer. I have applied your patch to my series.
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 11 lines · Rik van Riel
Quoted 4 lines · On Fri, 11 Jan 2008 15:24:34 +0900 KOSAKI Motohiro…
below patch is a bit cleanup proposal.
i thinkLRU_FILEis more clarify than "/2".What do you think it?
Thank you for the cleanup, your version looks a lot nicer. I have applied your patch to my series.
Rik:
I think we also want to do something like:
- BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3); + BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3 ||
+ NR_LRU_LISTS > 6);
Then we'll be warned if future change might break our implicit assumption that any lru_list value with '0x2' set is a file lru.
Lee
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 21 lines · On Fri, 11 Jan 2008 10:59:18 -0500 Lee Schermerhorn <[email protected]>…
Quoted 11 lines · Rik van Riel
Quoted 4 lines · On Fri, 11 Jan 2008 15:24:34 +0900 KOSAKI Motohiro…
below patch is a bit cleanup proposal.
i thinkLRU_FILEis more clarify than "/2".What do you think it?
Thank you for the cleanup, your version looks a lot nicer. I have applied your patch to my series.
Rik:
I think we also want to do something like:
(quoted diff) +2
-1- BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3); + BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3 || + NR_LRU_LISTS > 6);
Quoted 2 lines
Then we'll be warned if future change might break our implicit assumption that any
lru_listvalue with '0x2' set is a file lru.
Restoring the code to your original version makes things work again.
OTOH, I almost wonder if we should not simply define it to
return (l == LRU_INACTIVE_FILE || l == LRU_ACTIVE_FILE)
and just deal with it.
Your version of the code is correct and probably faster, but not as easy to read and probably not in a hot path :)
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 29 lines · Rik van Riel
Quoted 21 lines · On Fri, 11 Jan 2008 10:59:18 -0500 Lee Schermerhorn <[email protected]>…
Quoted 11 lines · Rik van Riel
Quoted 4 lines · On Fri, 11 Jan 2008 15:24:34 +0900 KOSAKI Motohiro…
below patch is a bit cleanup proposal.
i thinkLRU_FILEis more clarify than "/2".What do you think it?
Thank you for the cleanup, your version looks a lot nicer. I have applied your patch to my series.
Rik:
I think we also want to do something like:
(quoted diff) +2
-1- BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3); + BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3 || + NR_LRU_LISTS > 6);Quoted 2 lines
Then we'll be warned if future change might break our implicit assumption that any
lru_listvalue with '0x2' set is a file lru.Restoring the code to your original version makes things work again.
Quoted 8 lines
OTOH, I almost wonder if we should not simply define it to
return (l == LRU_INACTIVE_FILE || l == LRU_ACTIVE_FILE)and just deal with it.
Your version of the code is correct and probably faster, but not as easy to read and probably not in a hot path :)
Sure. Whatever you think will fly...
Lee
Quoted 1 line
Re: [patch 05/19] split LRU lists into anon & file sets
In reply to KOSAKI MotohiroQuoted 21 lines · KOSAKI Motohiro
Hi Rik
Review
Quoted 5 lines
(quoted diff) +5
-0+static inline int is_file_lru(enum lru_list l) +{ + BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3); + return (l/2 == 1); +}below patch is a bit cleanup proposal.
i thinkLRU_FILEis more clarify than "/2".What do you think it?
Index:
linux-2.6.24-rc6-mm1-rvr/include/linux/mmzone.h
===================================================================
include/linux/mmzone.h 2008-01-11 14:40:31.000000000 +0900 line 153
Quoted 8 lines
include/linux/mmzone.h 2008-01-11 14:40:31.000000000 +0900 renamed from include/linux/mmzone.h 2008-01-11 11:10:30.000000000 +0900 +1
-1@@ -147,7 +147,7 @@ static inline int is_file_lru(enum lru_list l) { BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3); - return (l/2 == 1); + return !!(l & LRU_FILE); } struct per_cpu_pages {
Kosaki-san:
Again, my doing. I agree that the calculation is a bit strange, but I wanted to "future-proof" this function in case we ever get to a value of '6' for the lru_list enum. In that case, the AND will evaluate to non-zero for what may not be a file LRU. Between the build time assertion and the division [which could just be a 'l >> 1', I suppose] we should be safe.
Thanks,
Lee
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 6 lines · On Fri, 11 Jan 2008 10:50:09 -0500 Lee Schermerhorn <[email protected]>…
Again, my doing. I agree that the calculation is a bit strange, but I wanted to "future-proof" this function in case we ever get to a value of '6' for the
lru_listenum. In that case, the AND will evaluate to non-zero for what may not be a file LRU. Between the build time assertion and the division [which could just be a 'l >> 1', I suppose] we should be safe.
Good point. I did not guess that.
I'll restore the code to your original test.
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
In reply to Rik van RielHi Rik
Quoted 1 line
(quoted diff) +0
-0@@ -1128,64 +1026,65 @@ static void shrink_active_list(unsigned
(snip)
Quoted 16 lines
(quoted diff) +6
-6+ /* + * For sorting active vs inactive pages, we'll use the 'anon' + * elements of the local list[] array and sort out the file vs + * anon pages below. + */ while (!list_empty(&l_hold)) { + lru = LRU_INACTIVE_ANON; cond_resched(); page = lru_to_page(&l_hold); list_del(&page->lru); - if (page_mapped(page)) { - if (!reclaim_mapped || - (total_swap_pages == 0 && PageAnon(page)) || - page_referenced(page, 0, sc->mem_cgroup)) { - list_add(&page->lru, &list[LRU_ACTIVE]); - continue;
Review
Quoted 10 lines
(quoted diff) +3
-6- } - } else if (TestClearPageReferenced(page)) { - list_add(&page->lru, &list[LRU_ACTIVE]); - continue; - } - list_add(&page->lru, &list[LRU_INACTIVE]); + if (page_referenced(page, 0, sc->mem_cgroup)) + lru = LRU_ACTIVE_ANON; + list_add(&page->lru, &list[lru]); }
Why drop (total_swap_pages == 0 && PageAnon(page)) condition?
in embedded sysmtem,CONFIG_NORECLAIM is OFF (because almost embedded cpu is 32bit) and that anon move to inactive list is meaningless because it doesn't have swap.
below code is more good, may be.
but I don't understand yet why ignore page_referenced() result at anon page ;-)
- kosaki
--- mm/vmscan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
mm/vmscan.c 2008-01-11 16:16:44.000000000 +0900 renamed from mm/vmscan.c 2008-01-11 13:59:12.000000000 +0900 +1 -1
@@ -1147,7 +1147,7 @@ static void shrink_active_list(unsigned } if (page_referenced(page, 0, sc->mem_cgroup)) { - if (file) + if (file || (total_swap_pages == 0)) /* Referenced file pages stay active. */ lru = LRU_ACTIVE_ANON; else
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 4 lines · On Fri, 11 Jan 2008 16:35:24 +0900 KOSAKI Motohiro…
Why drop (
total_swap_pages== 0 && PageAnon(page)) condition?
in embedded sysmtem,CONFIG_NORECLAIMis OFF (because almost embedded cpu is 32bit) and that anon move to inactive list is meaningless because it doesn't have swap.
That was a mistake, kind of. Since all swap backed pages are on their own LRU lists, we should not scan those lists at all any more if we are out of swap space.
The patch that fixes get_scan_ratio() adds that test.
Having said that, with the nr_swap_pages==0 test in get_scan_ratio(), we no longer need to test for that condition in shrink_active_list().
Quoted 2 lines
below code is more good, may be.
but I don't understand yet why ignorepage_referenced()result at anon page ;-)
On modern systems, swapping out anonymous pages is a relatively rare event. All anonymous pages start out as active and referenced, so testing for that condition does (1) not add any information and (2) mean we need to scan ALL of the anonymous pages, in order to find one candidate to swap out (since they are all referenced).
Simply deactivating a few pages and checking whether they were referenced again while on the (smaller) inactive_anon_list means we can find candidates to page out with a lot less CPU time used.
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Hi
Quoted 5 lines
Quoted 4 lines
Why drop (
total_swap_pages== 0 && PageAnon(page)) condition?
in embedded sysmtem,CONFIG_NORECLAIMis OFF (because almost embedded cpu is 32bit) and that anon move to inactive list is meaningless because it doesn't have swap.
Quoted 8 lines
That was a mistake, kind of. Since all swap backed pages are on their own LRU lists, we should not scan those lists at all any more if we are out of swap space.
The patch that fixes
get_scan_ratio()adds that test.Having said that, with the nr_swap_pages==0 test in
get_scan_ratio(), we no longer need to test for that condition inshrink_active_list().
Oh I see!
thank you for your kindful lecture.
your implementation is very cute.
Quoted 9 lines
Quoted 2 lines
below code is more good, may be.
but I don't understand yet why ignorepage_referenced()result at anon page ;-)On modern systems, swapping out anonymous pages is a relatively rare event. All anonymous pages start out as active and referenced, so testing for that condition does (1) not add any information and (2) mean we need to scan ALL of the anonymous pages, in order to find one candidate to swap out (since they are all referenced).
Quoted 3 lines
Simply deactivating a few pages and checking whether they were referenced again while on the (smaller)
inactive_anon_listmeans we can find candidates to page out with a lot less CPU time used.
thanks, I understand, may be.
- kosaki
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
In reply to Rik van RielHi Rik, Lee
I tested new hackbench on rvr split LRU patch.
http://people.redhat.com/mingo/cfs-scheduler/tools/hackbench.c
method of test
(1) $ ./hackbench 150 process 1000
(2) # sync; echo 3 > /proc/sys/vm/drop_caches
$ dd if=tmp10G of=/dev/null
$ ./hackbench 150 process 1000test machine
CPU: Itanium2 x4 (logical 8cpu)
MEM: 8GB
A. vanilla 2.6.24-rc8-mm1
(1) 127.540 (2) 727.548
B. 2.6.24-rc8-mm1 + split-lru-patch-series
(1) 92.730 (2) 758.369
comment:
(1) active/inactive anon ratio improve performance significant.
(2) incorrect page activation reduce performance.
I investigate reason and found reason is [05/19] change. I tested a bit porton reverted split-lru-patch-series again.
C. 2.6.24-rc8-mm1 + split-lru-patch-series + my-revert-patch
(1) 83.014
(2) 717.009
Of course, We need reintroduce this portion after new page LRU (aka LRU for used only page).
but now is too early.
I hope this patch series merge to -mm ASAP. therefore, I hope remove any corner case regression.
Thanks!
- kosaki
--- mm/vmscan.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-)
mm/vmscan.c 2008-01-30 11:53:42.000000000 +0900 renamed from mm/vmscan.c 2008-01-29 15:59:17.000000000 +0900 +25 -1
@@ -247,6 +247,27 @@ return ret; } +/* Called without lock on whether page is mapped, so answer is unstable */ +static inline int page_mapping_inuse(struct page *page) +{ + struct address_space *mapping; + + /* Page is in somebody's page tables. */ + if (page_mapped(page)) + return 1; + + /* Be more reluctant to reclaim swapcache than pagecache */ + if (PageSwapCache(page)) + return 1; + + mapping = page_mapping(page); + if (!mapping) + return 0; + + /* File is mmap'd by somebody? */ + return mapping_mapped(mapping); +} + static inline int is_page_cache_freeable(struct page *page) { return page_count(page) - !!PagePrivate(page) == 2;
@@ -515,7 +536,8 @@ referenced = page_referenced(page, 1, sc->mem_cgroup); /* In active use or really unfreeable? Activate it. */ - if (sc->order <= PAGE_ALLOC_COSTLY_ORDER && referenced) + if (sc->order <= PAGE_ALLOC_COSTLY_ORDER && + referenced && page_mapping_inuse(page)) goto activate_locked; #ifdef CONFIG_SWAP
@@ -550,6 +572,8 @@ } if (PageDirty(page)) { + if (sc->order <= PAGE_ALLOC_COSTLY_ORDER && referenced) + goto keep_locked; if (!may_enter_fs) { sc->nr_io_pages++; goto keep_locked;
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Hi Rik, Lee
I found number of scan pages calculation bug.
1. wrong calculation order
ap *= rotate_sum / (zone->recent_rotated_anon + 1);
when recent_rotated_anon = 100 and recent_rotated_file = 0,
rotate_sum / (zone->recent_rotated_anon + 1)
= 100 / 101
= 0
at that time, ap become 0.
2. wrong fraction omission
nr[l] = zone->nr_scan[l] * percent[file] / 100; when percent is very small, nr[l] become 0.
Test Result:
(1) $ ./hackbench 150 process 1000
(2) # sync; echo 3 > /proc/sys/vm/drop_caches
$ dd if=tmp10G of=/dev/null
$ ./hackbench 150 process 1000rvr-split-lru + revert patch of previous mail
(1) 83.014
(2) 717.009
rvr-split-lru + revert patch of previous mail + below patch
(1) 61.965 (2) 85.444 !!
Now, We got 1000% performance improvement against 2.6.24-rc8-mm1 :)
- kosaki
--- mm/vmscan.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
mm/vmscan.c +8 -3
@@ -1355,7 +1355,7 @@ static void get_scan_ratio(struct zone ** anon + file rotate_sum */ ap = (anon_prio * anon) / (anon + file +1 ); - ap *= rotate_sum / (zone->recent_rotated_anon +1 ); + ap = (ap * rotate_sum) / (zone->recent_rotated_anon +1 );if (ap ==0 ) ap =1 ;else if (ap >100 )
@@ -1363,7 +1363,7 @@ static void get_scan_ratio(struct zone * percent[0 ] = ap; fp = (file_prio * file) / (anon + file +1 ); - fp *= rotate_sum / (zone->recent_rotated_file +1 ); + fp = (fp * rotate_sum) / (zone->recent_rotated_file +1 );if (fp ==0 ) fp =1 ;else if (fp >100 )
@@ -1402,6 +1402,7 @@ static unsigned long shrink_zone(int prifor_each_reclaimable_lru (l) {if (scan_global_lru (sc)) { +unsigned long nr_max_scan;int file =is_file_lru (l);/* * Add one to nr_to_scan just to make sure that the
@@ -1409,7 +1410,11 @@ static unsigned long shrink_zone(int pri*/ zone->nr_scan[l] += (zone_page_state (zone,NR_INACTIVE_ANON + l) >> priority) +1 ; - nr[l] = zone->nr_scan[l] * percent[file] /100 ; + nr[l] = (zone->nr_scan[l] * percent[file] /100 ) +1 ; + nr_max_scan =zone_page_state (zone,NR_INACTIVE_ANON +l); +if (nr[l] > nr_max_scan) + nr[l] = nr_max_scan; +if (nr[l] >= sc->swap_cluster_max) zone->nr_scan[l] =0 ;else
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 38 lines · KOSAKI Motohiro
Hi Rik, Lee
I found number of scan pages calculation bug.
1. wrong calculation order
ap *= rotate_sum / (zone->recent_rotated_anon + 1);when recent_rotated_anon = 100 and recent_rotated_file = 0, rotate_sum / (zone->recent_rotated_anon + 1) = 100 / 101 = 0 at that time, ap become 0.2. wrong fraction omission
nr[l] = zone->nr_scan[l] * percent[file] / 100; when percent is very small, nr[l] become 0.Test Result:
(1) $ ./hackbench 150 process 1000
(2) # sync; echo 3 >/proc/sys/vm/drop_caches$ dd if=tmp10G of=/dev/null $ ./hackbench 150 process 1000rvr-split-lru + revert patch of previous mail
(1) 83.014(2) 717.009rvr-split-lru + revert patch of previous mail + below patch
(1) 61.965 (2) 85.444 !!
Quoted 8 lines
Now, We got 1000% performance improvement against 2.6.24-rc8-mm1 :)
- kosaki
Signed-off-by KOSAKI Motohiro <[email protected]>
<snip>
Kosaki-san:
Rik is currently out on holiday and I've been traveling. Just getting back to rebasing to 24-rc8-mm1. Thank you for your efforts in testing and tracking down the regressions. I will add your fixes into my tree and try them out and let you know. Rik mentioned to me that he has a fix for the "get_scan_ratio()" calculation that is causing us to OOM kill prematurely--i.e., when we still have lots of swap space to evict swappable anon. I don't know if it's similar to what you have posted. Have to wait and see what he says. Meantime, we'll try your patches.
Again, thank you.
Regards,
Lee
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Hi Lee-san
Quoted 8 lines
Rik is currently out on holiday and I've been traveling. Just getting back to rebasing to 24-rc8-mm1. Thank you for your efforts in testing and tracking down the regressions. I will add your fixes into my tree and try them out and let you know. Rik mentioned to me that he has a fix for the "
get_scan_ratio()" calculation that is causing us to OOM kill prematurely--i.e., when we still have lots of swap space to evict swappable anon. I don't know if it's similar to what you have posted. Have to wait and see what he says. Meantime, we'll try your patches.
thank you for your quick response.
on my test environment, my patch solve incorrect OOM. because, too small reclaim cause OOM.
Please confirm.
- kosaki
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 2 lines · On Thu, 31 Jan 2008 10:17:48 +0900 KOSAKI Motohiro…
on my test environment, my patch solve incorrect OOM. because, too small reclaim cause OOM.
That makes sense.
The version you two are looking at can return "percentages" way larger than 100 in get_scan_ratio.
A fixed version of get_scan_ratio, where the
percentages always add up to 100%, makes the
system go OOM before it seriously starts
swapping.
I will integrate your fixes with my code when I get back from holidays. Then things should work :)
Thank you for your analysis of the problem.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 4 lines
I will integrate your fixes with my code when I get back from holidays. Then things should work :)
Thank you for your analysis of the problem.
Thank you.
enjoy good vacation :)
-
kosaki
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
In reply to KOSAKI MotohiroQuoted 1 line · On Wed, 30 Jan 2008 17:57:54 +0900 KOSAKI Motohiro…
I found number of scan pages calculation bug.
My latest version of get_scan_ratio() works differently, with the percentages always adding up to 100. However, your patch gave me the inspiration to (hopefully) find the bug in my version of the code.
Quoted 1 line
1. wrong calculation order
I do not believe my new code has this problem. Of course, this is purely due to luck :)
Quoted 6 lines
2. wrong fraction omission
nr[l] = zone->nr_scan[l] * percent[file] / 100; when percent is very small, nr[l] become 0.
This is probably where the problem is. Kind of.
I believe that the problem is that we scale nr[l] by the percentage, instead of scaling the amount we add to zone->nr_scan[l] by the percentage!
Review static unsigned long shrink_zone(int pri · line 1420
Quoted 13 lines
(quoted diff) +5
-1@@ -1409,7 +1410,11 @@ static unsigned long shrink_zone(int pri */ zone->nr_scan[l] += (zone_page_state(zone, NR_INACTIVE_ANON + l) >> priority) + 1; - nr[l] = zone->nr_scan[l] * percent[file] / 100; + nr[l] = (zone->nr_scan[l] * percent[file] / 100) + 1; + nr_max_scan = zone_page_state(zone, NR_INACTIVE_ANON+l); + if (nr[l] > nr_max_scan) + nr[l] = nr_max_scan; + if (nr[l] >= sc->swap_cluster_max) zone->nr_scan[l] = 0; else
With the fix below (against my latest tree), we always add at least one to zone->nr_scan[l] and always make that increment count later on!
I am still recovering from my trip home (thanks to the airline companies I spent 25 hours travelling, from door to door), so I may not get around to actually testing this today:
mm/vmscan.c +8 -4
@@ -1275,13 +1275,17 @@ static unsigned long shrink_zone(int prifor_each_lru (l) {if (scan_global_lru (sc)) {int file =is_file_lru (l); +int scan;/* * Add one to nr_to_scan just to make sure that the -* kernel will slowly sift through the active list. +* kernel will slowly sift through each list. */ - zone->nr_scan[l] += (zone_page_state (zone, -NR_INACTIVE_ANON + l) >> priority) +1 ; - nr[l] = zone->nr_scan[l] * percent[file] /100 ; + scan =zone_page_state (zone,NR_INACTIVE_ANON + l); + scan >>= priority; + scan = (scan * percent[file]) /100 ; + + zone->nr_scan[l] += scan +1 ; + nr[l] = zone->nr_scan[l];if (nr[l] >= sc->swap_cluster_max) zone->nr_scan[l] =0 ;else
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Hi Rik
Welcome back :)
Quoted 6 lines
Quoted 1 line
I found number of scan pages calculation bug.
My latest version of
get_scan_ratio()works differently, with the percentages always adding up to 100. However, your patch gave me the inspiration to (hopefully) find the bug in my version of the code.
OK.
Quoted 4 lines
Quoted 4 lines
2. wrong fraction omission
nr[l] = zone->nr_scan[l] * percent[file] / 100;
Quoted 8 lines
Quoted 2 lines
when percent is very small, nr[l] become 0.This is probably where the problem is. Kind of.
I believe that the problem is that we scale nr[l] by the percentage, instead of scaling the amount we add to zone->nr_scan[l] by the percentage!
Aahh,
you are right.
Quoted 16 lines
Index:
linux-2.6.24-rc6-mm1/mm/vmscan.c
===================================================================mm/vmscan.c +2
-3@@ -1275,13 +1275,17 @@ static unsigned long shrink_zone(int prifor_each_lru (l) {if (scan_global_lru (sc)) {int file =is_file_lru (l); +int scan;/* * Add one to nr_to_scan just to make sure that the -* kernel will slowly sift through the active list. +* kernel will slowly sift through each list. */ - zone->nr_scan[l] += (zone_page_state (zone, -NR_INACTIVE_ANON + l) >> priority) +1 ;
mm/vmscan.c static unsigned long shrink_zone(int pri · line 1291
Quoted 10 lines
mm/vmscan.c +6
-1- nr[l] = zone->nr_scan[l] * percent[file] /100 ; + scan =zone_page_state (zone,NR_INACTIVE_ANON + l); + scan >>= priority; + scan = (scan * percent[file]) /100 ; + + zone->nr_scan[l] += scan +1 ; + nr[l] = zone->nr_scan[l];if (nr[l] >= sc->swap_cluster_max) zone->nr_scan[l] =0 ;else
looks good.
thank you clean up code.
- kosaki
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 05/19] split LRU lists into anon & file sets
Quoted 2 lines · On Thu, 07 Feb 2008 10:20:39 +0900 KOSAKI Motohiro…
looks good.
thank you clean up code.
Yeah, it looks good.
Too bad it still does not work :)
Oh well, I'll look at that tomorrow. Jet lag is catching up with me, so I should get some rest first...
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 6/19 SEQ replacement for anonymous pages
In reply to Rik van RielWe avoid evicting and scanning anonymous pages for the most part, but under some workloads we can end up with most of memory filled with anonymous pages. At that point, we suddenly need to clear the referenced bits on all of memory, which can take ages on very large memory systems.
We can reduce the maximum number of pages that need to be scanned by not taking the referenced state into account when deactivating an anonymous page. After all, every anonymous page starts out referenced, so why check?
If an anonymous page gets referenced again before it reaches the end of the inactive list, we move it back to the active list.
To keep the maximum amount of necessary work reasonable, we scale the active to inactive ratio with the size of memory, using the formula active:inactive ratio = sqrt(memory in GB * 10).
Kswapd CPU use now seems to scale by the amount of pageout bandwidth, instead of by the amount of memory present in the system.
include/linux/mm_inline.h +12 -0
@@ -106,4 +106,16 @@ del_page_from_lru(struct zone *zone, str __dec_zone_state(zone, NR_INACTIVE_ANON + l); } +static inline int inactive_anon_low (struct zone *zone) +{ +unsigned long active, inactive; + + active =zone_page_state (zone,NR_ACTIVE_ANON ); + inactive =zone_page_state (zone,NR_INACTIVE_ANON ); + +if (inactive * zone->inactive_ratio < active) +return 1 ; + +return 0 ; +}#endif
include/linux/mmzone.h +5 -0
@@ -313,6 +313,11 @@ struct zone {*/ int prev_priority; +/* +* The ratio of active to inactive pages. +*/ +unsigned int inactive_ratio; +ZONE_PADDING (_pad2_)/* Rarely used or read-mostly fields */
mm/page_alloc.c +40 -0
@@ -4230,6 +4230,45 @@ void setup_per_zone_pages_min(void)calculate_totalreserve_pages (); } +/** +* setup_per_zone_inactive_ratio - called when min_free_kbytes changes. +* +* The inactive anon list should be small enough that the VM never has to +* do too much work, but large enough that each inactive page has a chance +* to be referenced again before it is swapped out. +* +* The inactive_anon ratio is the ratio of active to inactive anonymous +* pages. Ie. a ratio of 3 means 3:1 or 25% of the anonymous pages are +* on the inactive list. +* +* total return max +* memory value inactive anon +* ------------------------------------- +* 10MB 1 5MB +* 100MB 1 50MB +* 1GB 3 250MB +* 10GB 10 0.9GB +* 100GB 31 3GB +* 1TB 101 10GB +* 10TB 320 32GB +*/ +void setup_per_zone_inactive_ratio (void ) +{ +struct zone *zone; + +for_each_zone (zone) { +unsigned int gb, ratio; + +/* Zone size in gigabytes */ + gb = zone->present_pages >> (30 -PAGE_SHIFT ); + ratio =int_sqrt (10 * gb); +if (!ratio) + ratio =1 ; + + zone->inactive_ratio = ratio; + } +} +/* * Initialise min_free_kbytes. *
@@ -4267,6 +4306,7 @@ static int __init init_per_zone_pages_mi min_free_kbytes =65536 ;setup_per_zone_pages_min ();setup_per_zone_lowmem_reserve (); +setup_per_zone_inactive_ratio ();return 0 ; }module_init (init_per_zone_pages_min)
mm/vmscan.c +31 -6
@@ -1019,7 +1019,7 @@ static inline int zone_is_near_oom(strucstatic void shrink_active_list (unsigned long nr_pages,struct zone *zone,struct scan_control *sc,int priority,int file) { -unsigned long pgmoved; +unsigned long pgmoved =0 ;int pgdeactivate =0 ;unsigned long pgscanned;LIST_HEAD (l_hold);/* The pages which were snipped off */
@@ -1058,12 +1058,25 @@ static void shrink_active_list(unsignedcond_resched (); page =lru_to_page (&l_hold);list_del (&page->lru); -if (page_referenced (page,0 , sc->mem_cgroup)) - lru =LRU_ACTIVE_ANON ; +if (page_referenced (page,0 , sc->mem_cgroup)) { +if (file) +/* Referenced file pages stay active. */ + lru =LRU_ACTIVE_ANON ; +else +/* Anonymous pages always get deactivated. */ + pgmoved++; + }list_add (&page->lru, &list[lru]); }/* +* Count the referenced anon pages as rotated, to balance pageout +* scan pressure between file and anonymous pages in get_scan_ratio. +*/ +if (!file) + zone->recent_rotated_anon += pgmoved; + +/* * Now put the pages back to the appropriate [file or anon] inactive * and active lists. */
@@ -1145,7 +1158,11 @@ static unsigned long shrink_list(enum lr {int file =is_file_lru (lru); -if (lru ==LRU_ACTIVE_ANON || lru ==LRU_ACTIVE_FILE ) { +if (lru ==LRU_ACTIVE_FILE ) { +shrink_active_list (nr_to_scan, zone, sc, priority, file); +return 0 ; + } +if (lru ==LRU_ACTIVE_ANON &&inactive_anon_low (zone)) {shrink_active_list (nr_to_scan, zone, sc, priority, file);return 0 ; }
@@ -1255,8 +1272,8 @@ static unsigned long shrink_zone(int pri } } -while (nr[LRU_ACTIVE_ANON ] || nr[LRU_INACTIVE_ANON ] || - nr[LRU_ACTIVE_FILE ] || nr[LRU_INACTIVE_FILE ]) { +while (nr[LRU_INACTIVE_ANON ] || nr[LRU_ACTIVE_FILE ] || + nr[LRU_INACTIVE_FILE ]) {for_each_lru (l) {if (nr[l]) { nr_to_scan = min(nr[l],
@@ -1560,6 +1577,14 @@ loop_again: priority != DEF_PRIORITY)continue ; +/* +* Do some background aging of the anon list, to give +* pages a chance to be referenced before reclaiming. +*/ +if (inactive_anon_low (zone)) +shrink_active_list (SWAP_CLUSTER_MAX , zone, + &sc, priority,0 ); +if (!zone_watermark_ok (zone, order, zone->pages_high,0 ,0 )) { end_zone = i;
mm/vmstat.c +4 -2
@@ -800,10 +800,12 @@ static void zoneinfo_show_print(struct sseq_printf (m,"\n all_unreclaimable: %u" "\n prev_priority: %i" -"\n start_pfn: %lu" , +"\n start_pfn: %lu" +"\n inactive_ratio: %u" ,zone_is_all_unreclaimable (zone), zone->prev_priority, - zone->zone_start_pfn); + zone->zone_start_pfn, + zone->inactive_ratio);seq_putc (m,'\n' ); }
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 7/19 (NEW) add some sanity checks to get_scan_ratio
In reply to Rik van RielThe access ratio based scan rate determination in get_scan_ratio works ok in most situations, but needs to be corrected in some corner cases:
- if we run out of swap space, do not bother scanning the anon LRUs
- if we have already freed all of the page cache, we need to scan the anon LRUs
mm/vmscan.c +15 -1
@@ -1182,7 +1182,7 @@ static unsigned long shrink_list(enum lrstatic void get_scan_ratio (struct zone *zone,struct scan_control * sc,unsigned long *percent) { -unsigned long anon, file; +unsigned long anon, file, free;unsigned long anon_prio, file_prio;unsigned long rotate_sum;unsigned long ap, fp;
@@ -1230,6 +1230,20 @@ static void get_scan_ratio(struct zone *else if (fp >100 ) fp =100 ; percent[1 ] = fp; + + free =zone_page_state (zone,NR_FREE_PAGES ); + +/* +* If we have no swap space, do not bother scanning anon pages +*/ +if (nr_swap_pages <=0 ) + percent[0 ] =0 ; +/* +* If we already freed most file pages, scan the anon pages +* regardless of the page access ratios or swappiness setting. +*/ +else if (file + free <= zone->pages_high) + percent[0 ] =100 ; }
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 07/19] (NEW) add some sanity checks to get_scan_ratio
Quoted 24 lines · On Tue, 08 Jan 2008 15:59:46 -0500 Rik van Riel <[email protected]> wrote:
The access ratio based scan rate determination in
get_scan_ratioworks ok in most situations, but needs to be corrected in some corner cases:
- if we run out of swap space, do not bother scanning the anon LRUs
- if we have already freed all of the page cache, we need to scan the anon LRUsSigned-off-by Rik van Riel <[email protected]>Index:
linux-2.6.24-rc6-mm1/mm/vmscan.c
===================================================================mm/vmscan.c +1
-1@@ -1182,7 +1182,7 @@ static unsigned long shrink_list(enum lrstatic void get_scan_ratio (struct zone *zone,struct scan_control * sc,unsigned long *percent) { -unsigned long anon, file; +unsigned long anon, file, free;unsigned long anon_prio, file_prio;unsigned long rotate_sum;unsigned long ap, fp;@@ -1230,6 +1230,20 @@ static void get_scan_ratio(struct zone *else if (fp >100 )
mm/vmscan.c static void get_scan_ratio(struct zone * · line 1240
Quoted 10 lines
mm/vmscan.c +8
-0fp =100 ; percent[1 ] = fp; + + free =zone_page_state (zone,NR_FREE_PAGES ); + +/* +* If we have no swap space, do not bother scanning anon pages +*/ +if (nr_swap_pages <=0 ) + percent[0 ] =0 ;
Doesn't this mean that swap-cache in ACTIVE_ANON_LIST is not scanned ? Or swap-cache is in File-Cache list ?
Thanks,
-Kame
Re: [patch 07/19] (NEW) add some sanity checks to get_scan_ratio
Quoted 10 lines · On Wed, 9 Jan 2008 13:16:42 +0900 KAMEZAWA Hiroyuki…
mm/vmscan.c static void get_scan_ratio(struct zone * · line 1240
Quoted 8 lines
mm/vmscan.c +8
-0+ + free =zone_page_state (zone,NR_FREE_PAGES ); + +/* +* If we have no swap space, do not bother scanning anon pages +*/ +if (nr_swap_pages <=0 ) + percent[0 ] =0 ;Doesn't this mean that swap-cache in
ACTIVE_ANON_LISTis not scanned ? Or swap-cache is in File-Cache list ?
You are right, the swap cache will not be scanned once we run completely out of swap space. To compensate for that, this patch series has a patch that does scanning of swap cache and freeing of swap space used by pages on the LRU list while there is still space free.
Scanning all of the anon LRU lists could be a lot of work for very little gain. A typical large server will have 32GB or more of RAM, but only the default 2GB of swap.
All we accomplish by scanning the anonymous memory on a system like that (once swap is full) is eating up CPU time and causing lock contention.
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 8/19 add newly swapped in pages to the inactive list
In reply to Rik van RielSwapin_readahead can read in a lot of data that the processes in memory never need. Adding swap cache pages to the inactive list prevents them from putting too much pressure on the working set.
This has the potential to help the programs that are already in memory, but it could also be a disadvantage to processes that are trying to get swapped in.
In short, this patch needs testing.
mm/swap_state.c +1 -1
@@ -300,7 +300,7 @@ struct page *read_swap_cache_async(swp_e/* * Initiate read into locked page and return. */ -lru_cache_add_active_anon (new_page); +lru_cache_add_anon (new_page);swap_readpage (NULL , new_page);return new_page; }
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 08/19] add newly swapped in pages to the inactive list
Quoted 1 line · Rik van Riel
In short, this patch needs testing.
Seems to be a good idea.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 9/19 (NEW) more aggressively use lumpy reclaim
In reply to Rik van RielDuring an AIM7 run on a 16GB system, fork started failing around 32000 threads, despite the system having plenty of free swap and 15GB of pageable memory.
If normal pageout does not result in contiguous free pages for kernel stacks, fall back to lumpy reclaim instead of failing fork or doing excessive pageout IO.
I do not know whether this change is needed due to the extreme stress test or because the inactive list is a smaller fraction of system memory on huge systems.
mm/vmscan.c +16 -4
@@ -870,7 +870,8 @@ int isolate_lru_page(struct page *page)* of reclaimed pages */ static unsigned long shrink_inactive_list (unsigned long max_scan, -struct zone *zone,struct scan_control *sc,int file) +struct zone *zone,struct scan_control *sc, +int priority,int file) {LIST_HEAD (page_list);struct pagevec pvec;
@@ -888,8 +889,19 @@ static unsigned long shrink_inactive_lisunsigned long nr_freed;unsigned long nr_active;unsigned int count[NR_LRU_LISTS ] = {0 , }; -int mode = (sc->order >PAGE_ALLOC_COSTLY_ORDER ) ? -ISOLATE_BOTH :ISOLATE_INACTIVE ; +int mode =ISOLATE_INACTIVE ; + +/* +* If we need a large contiguous chunk of memory, or have +* trouble getting a small set of contiguous pages, we +* will reclaim both active and inactive pages. +* +* We use the same threshold as pageout congestion_wait below. +*/ +if (sc->order >PAGE_ALLOC_COSTLY_ORDER ) + mode =ISOLATE_BOTH ; +else if (sc->order && priority <DEF_PRIORITY -2 ) + mode =ISOLATE_BOTH ; nr_taken = sc->isolate_pages(sc->swap_cluster_max, &page_list, &nr_scan, sc->order, mode,
@@ -1166,7 +1178,7 @@ static unsigned long shrink_list(enum lrshrink_active_list (nr_to_scan, zone, sc, priority, file);return 0 ; } -return shrink_inactive_list (nr_to_scan, zone, sc, file); +return shrink_inactive_list (nr_to_scan, zone, sc, priority, file); }/*
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 09/19] (NEW) more aggressively use lumpy reclaim
Quoted 3 lines · Rik van Riel
If normal pageout does not result in contiguous free pages for kernel stacks, fall back to lumpy reclaim instead of failing fork or doing excessive pageout IO.
Good. Ccing Mel. This is going to help higher order pages which is useful for a couple of other projects.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Mel Gorman
Acked-byRe: [patch 09/19] (NEW) more aggressively use lumpy reclaim
On (08/01/08 14:30), Christoph Lameter didst pronounce:
Quoted 9 lines · Rik van Riel
Quoted 4 lines
If normal pageout does not result in contiguous free pages for kernel stacks, fall back to lumpy reclaim instead of failing fork or doing excessive pageout IO.
Good. Ccing Mel. This is going to help higher order pages which is useful for a couple of other projects.
Well, the patch only has any impact when the order you are reclaiming is less than PAGE_ALLOC_COSTLY_ORDER so I would not have considered it of major impact to other projects interested in high order allocations. However, in isolation I have no problem with this patch and I can see how it makes sense for the problem scenario described. I rebased just this patch to 2.6.24-rc7 and found no problems but I have not had the chance to review the whole set.
Quoted 2 lines
Reviewed-by Christoph Lameter <[email protected]>
Signature · 9 lines
Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 10/19 No Reclaim LRU Infrastructure
In reply to Rik van RielV1 -> V3:
+ rebase to 23-mm1 atop RvR's split LRU series
+ define NR_NORECLAIM and LRU_NORECLAIM to avoid errors when not configured.
V1 -> V2:
+ handle review comments -- various typos and errors.
+ extract "putback_all_noreclaim_pages()" into a separate patch and rework as "scan_all_zones_noreclaim_pages().
Infrastructure to manage pages excluded from reclaim--i.e., hidden from vmscan. Based on a patch by Larry Woodman of Red Hat. Reworked to maintain "nonreclaimable" pages on a separate per-zone LRU list, to "hide" them from vmscan. A separate noreclaim pagevec is provided for shrink_active_list() to move nonreclaimable pages to the noreclaim list without over burdening the zone lru_lock.
Pages on the noreclaim list have both PG_noreclaim and PG_lru set. Thus, PG_noreclaim is analogous to and mutually exclusive with PG_active--it specifies which LRU list the page is on.
The noreclaim infrastructure is enabled by a new mm Kconfig option [CONFIG_]NORECLAIM.
A new function 'page_reclaimable(page, vma)' in vmscan.c tests whether or not a page is reclaimable. Subsequent patches will add the various !reclaimable tests. We'll want to keep these tests light-weight for use in shrink_active_list() and, possibly, the fault path.
Notes:
1. for now, use bit 30 in page flags. This restricts the no reclaim infrastructure to 64-bit systems. [The mlock patch, later in this series, uses another of these 64-bit-system-only flags.]
Rationale: 32-bit systems have no free page flags and are less likely to have the large amounts of memory that exhibit the problems this series attempts to solve. [I'm sure someone will disabuse me of this notion.]
Thus, NORECLAIM currently depends on [CONFIG_]64BIT.
2. The pagevec to move pages to the noreclaim list results in another loop at the end of shrink_active_list(). If we ultimately adopt Rik van Riel's split lru approach, I think we'll need to find a way to factor all of these loops into some common code.
3. TODO: Memory Controllers maintain separate active and inactive lists. Need to consider whether they should also maintain a noreclaim list. Also, convert to use Christoph's array of indexed lru variables?
See //TODO note in mm/memcontrol.c re: isolating non-reclaimable pages.
4. TODO: more factoring of lru list handling. But, I want to get this as close to functionally correct as possible before introducing those perturbations.
mm/Kconfig +10 -0
@@ -193,3 +193,13 @@ config NR_QUICK config VIRT_TO_BUS def_bool y depends on !ARCH_NO_VIRT_TO_BUS + +config NORECLAIM + bool "Track non-reclaimable pages (EXPERIMENTAL; 64BIT only)" + depends on EXPERIMENTAL && 64BIT + help + Supports tracking of non-reclaimable pages off the [in]active lists + to avoid excessive reclaim overhead on large memory systems. Pages + may be non-reclaimable because: they are locked into memory, they + are anonymous pages for which no swap space exists, or they are anon + pages that are expensive to unmap [long anon_vma "related vma" list.]
include/linux/page-flags.h +19 -0
@@ -94,6 +94,7 @@/* PG_readahead is only used for file reads; PG_reclaim is only for writes */ #define PG_readahead PG_reclaim/* Reminder to do async read-ahead */ +/* PG_owner_priv_1 users should have descriptive aliases */ #define PG_checked PG_owner_priv_1/* Used by some filesystems */ #define PG_pinned PG_owner_priv_1/* Xen pinned pagetable */
@@ -107,6 +108,8 @@* 63 32 0 */ #define PG_uncached 31/* Page has been mapped as uncached */ + +#define PG_noreclaim 30/* Page is "non-reclaimable" */ #endif /*
@@ -160,6 +163,7 @@ static inline void SetPageUptodate(struc#define SetPageActive (page) set_bit(PG_active, &(page)->flags)#define ClearPageActive (page) clear_bit(PG_active, &(page)->flags)#define __ClearPageActive (page) __clear_bit(PG_active, &(page)->flags) +#define TestClearPageActive (page) test_and_clear_bit(PG_active, &(page)->flags)#define PageSlab (page) test_bit(PG_slab, &(page)->flags)#define __SetPageSlab (page) __set_bit(PG_slab, &(page)->flags)
@@ -261,6 +265,21 @@ static inline void __ClearPageTail(struc#define PageSwapCache (page) 0#endif +#ifdef CONFIG_NORECLAIM +#define PageNoreclaim (page) test_bit(PG_noreclaim, &(page)->flags) +#define SetPageNoreclaim (page) set_bit(PG_noreclaim, &(page)->flags) +#define ClearPageNoreclaim (page) clear_bit(PG_noreclaim, &(page)->flags) +#define __ClearPageNoreclaim (page) __clear_bit(PG_noreclaim, &(page)->flags) +#define TestClearPageNoreclaim (page) test_and_clear_bit(PG_noreclaim, \ + &(page)->flags) +#else +#define PageNoreclaim (page) 0 +#define SetPageNoreclaim (page) +#define ClearPageNoreclaim (page) +#define __ClearPageNoreclaim (page) +#define TestClearPageNoreclaim (page) 0 +#endif +#define PageUncached (page) test_bit(PG_uncached, &(page)->flags)#define SetPageUncached (page) set_bit(PG_uncached, &(page)->flags)#define ClearPageUncached (page) clear_bit(PG_uncached, &(page)->flags)
include/linux/mmzone.h +14 -1
@@ -84,6 +84,11 @@ enum zone_stat_item {NR_ACTIVE_ANON ,/* " " " " " */ NR_INACTIVE_FILE ,/* " " " " " */ NR_ACTIVE_FILE ,/* " " " " " */ +#ifdef CONFIG_NORECLAIM +NR_NORECLAIM ,/* " " " " " */ +#else +NR_NORECLAIM =NR_ACTIVE_FILE ,/* avoid compiler errors in dead code */ +#endifNR_ANON_PAGES ,/* Mapped anonymous pages */ NR_FILE_MAPPED ,/* pagecache pages mapped into pagetables. only modified from process context */
@@ -123,10 +128,18 @@ enum lru_list {LRU_ACTIVE_ANON =LRU_BASE +LRU_ACTIVE ,LRU_INACTIVE_FILE =LRU_BASE +LRU_FILE ,LRU_ACTIVE_FILE =LRU_BASE +LRU_FILE +LRU_ACTIVE , - NR_LRU_LISTS }; +#ifdef CONFIG_NORECLAIM +LRU_NORECLAIM , +#else +LRU_NORECLAIM =LRU_ACTIVE_FILE ,/* avoid compiler errors in dead code */ +#endif + NR_LRU_LISTS +};#define for_each_lru (l) for (l = 0; l < NR_LRU_LISTS; l++) +#define for_each_reclaimable_lru (l) for (l = 0; l <= LRU_ACTIVE_FILE; l++) +static inline int is_file_lru (enum lru_list l) {BUILD_BUG_ON (LRU_INACTIVE_FILE !=2 ||LRU_ACTIVE_FILE !=3 );
mm/page_alloc.c +9 -0
@@ -248,6 +248,9 @@ static void bad_page(struct page *page) 1 << PG_private | 1 << PG_locked | 1 << PG_active | +#ifdef CONFIG_NORECLAIM + 1 << PG_noreclaim | +#endif 1 << PG_dirty | 1 << PG_reclaim | 1 << PG_slab |
@@ -482,6 +485,9 @@ static inline int free_pages_check(struc 1 << PG_swapcache | 1 << PG_writeback | 1 << PG_reserved | +#ifdef CONFIG_NORECLAIM + 1 << PG_noreclaim | +#endif 1 << PG_buddy ))))bad_page (page);if (PageDirty (page))
@@ -629,6 +635,9 @@ static int prep_new_page(struct page *pa 1 << PG_private | 1 << PG_locked | 1 << PG_active | +#ifdef CONFIG_NORECLAIM + 1 << PG_noreclaim | +#endif 1 << PG_dirty | 1 << PG_slab | 1 << PG_swapcache |
include/linux/mm_inline.h +24 -1
@@ -82,13 +82,36 @@ del_page_from_inactive_file_list(structdel_page_from_lru_list (zone, page,LRU_INACTIVE_FILE ); } +#ifdef CONFIG_NORECLAIM +static inline void +add_page_to_noreclaim_list (struct zone *zone,struct page *page) +{ +add_page_to_lru_list (zone, page,LRU_NORECLAIM ); +} + +static inline void +del_page_from_noreclaim_list (struct zone *zone,struct page *page) +{ +del_page_from_lru_list (zone, page,LRU_NORECLAIM ); +} +#else +static inline void +add_page_to_noreclaim_list (struct zone *zone,struct page *page) { } + +static inline void +del_page_from_noreclaim_list (struct zone *zone,struct page *page) { } +#endif +static inline void del_page_from_lru (struct zone *zone,struct page *page) {enum lru_list l =LRU_INACTIVE_ANON ;list_del (&page->lru); -if (PageActive (page)) { +if (PageNoreclaim (page)) { +__ClearPageNoreclaim (page); + l =LRU_NORECLAIM ; + }else if (PageActive (page)) {__ClearPageActive (page); l =LRU_ACTIVE_ANON ; }
include/linux/swap.h +17 -0
@@ -175,6 +175,13 @@ extern void FASTCALL(lru_cache_add_file(extern void FASTCALL (lru_cache_add_anon (struct page *));extern void FASTCALL (lru_cache_add_active_file (struct page *));extern void FASTCALL (lru_cache_add_active_anon (struct page *)); +extern void FASTCALL (lru_cache_add_active_or_noreclaim (struct page *page, +struct vm_area_struct *vma)); +#ifdef CONFIG_NORECLAIM +extern void FASTCALL (lru_cache_add_noreclaim (struct page *page)); +#else +static inline void lru_cache_add_noreclaim (struct page *page) { } +#endif extern void FASTCALL (activate_page (struct page *));extern void FASTCALL (mark_page_accessed (struct page *));extern void lru_add_drain (void );
@@ -206,6 +213,16 @@ static inline int zone_reclaim(struct zo }#endif +#ifdef CONFIG_NORECLAIM +extern int page_reclaimable (struct page *page,struct vm_area_struct *vma); +#else +static inline int page_reclaimable (struct page *page, +struct vm_area_struct *vma) +{ +return 1 ; +} +#endif +extern int kswapd_run (int nid);#ifdef CONFIG_MMU
include/linux/pagevec.h +5 -0
@@ -27,6 +27,11 @@ void __pagevec_lru_add_file(struct pagevvoid __pagevec_lru_add_active_file (struct pagevec *pvec);void __pagevec_lru_add_anon (struct pagevec *pvec);void __pagevec_lru_add_active_anon (struct pagevec *pvec); +#ifdef CONFIG_NORECLAIM +void __pagevec_lru_add_noreclaim (struct pagevec *pvec); +#else +static inline void __pagevec_lru_add_noreclaim (struct pagevec *pvec) { } +#endif void pagevec_strip (struct pagevec *pvec);void pagevec_swap_free (struct pagevec *pvec); unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
mm/swap.c +89 -7
162 lines not on this page · raw message
mm/migrate.c +15 -3
@@ -52,9 +52,18 @@ int migrate_prep(void)return 0 ; } +/* +* move_to_lru() - place @page onto appropriate lru list +* based on preserved page flags: active, noreclaim, none +*/ static inline void move_to_lru (struct page *page) { -if (PageActive (page)) { +if (PageNoreclaim (page)) { +VM_BUG_ON (PageActive (page)); +ClearPageNoreclaim (page); +lru_cache_add_noreclaim (page); + }else if (PageActive (page)) { +VM_BUG_ON (PageNoreclaim (page));/* race ? */ /* * lru_cache_add_active checks that * the PG_active bit is off.
@@ -65,6 +74,7 @@ static inline void move_to_lru(struct paelse lru_cache_add_active_anon (page); }else { +VM_BUG_ON (PageNoreclaim (page));/* race ? */ if (page_file_cache (page))lru_cache_add_file (page);else
@@ -341,8 +351,11 @@ static void migrate_page_copy(struct pagSetPageReferenced (newpage);if (PageUptodate (page))SetPageUptodate (newpage); -if (PageActive (page)) +if (TestClearPageActive (page)) { +VM_BUG_ON (PageNoreclaim (page));SetPageActive (newpage); + }else if (TestClearPageNoreclaim (page)) +SetPageNoreclaim (newpage);if (PageChecked (page))SetPageChecked (newpage);if (PageMappedToDisk (page))
@@ -356,7 +369,6 @@ static void migrate_page_copy(struct pag#ifdef CONFIG_SWAP ClearPageSwapCache (page);#endif -ClearPageActive (page);ClearPagePrivate (page);set_page_private (page,0 ); page->mapping =NULL ;
mm/vmscan.c +102 -16
202 lines not on this page · raw message
mm/mempolicy.c +1 -1
@@ -1912,7 +1912,7 @@ static void gather_stats(struct page *paif (PageSwapCache (page)) md->swapcache++; -if (PageActive (page)) +if (PageActive (page) ||PageNoreclaim (page)) md->active++;if (PageWriteback (page))
mm/memcontrol.c +4 -0
@@ -520,6 +520,10 @@ unsigned long mem_cgroup_isolate_pages(u scan++;list_move (&pc->lru, &pc_list); +//TODO: for now, don't isolate non-reclaimable pages. When/if +// mem controller supports a noreclaim list, we'll need to make +// at least ISOLATE_ACTIVE visible outside of vm_scan and pass +// the 'take_nonreclaimable' flag accordingly. if (__isolate_lru_page (page, mode, file) ==0 ) {list_move (&page->lru, dst); nr_taken++;
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 10/19] No Reclaim LRU Infrastructure
Hi Rik
mm/Kconfig config NR_QUICK · line 205
Quoted 9 lines
mm/Kconfig +9
-0+config NORECLAIM + bool "Track non-reclaimable pages (EXPERIMENTAL; 64BIT only)" + depends on EXPERIMENTAL && 64BIT + help + Supports tracking of non-reclaimable pages off the [in]active lists + to avoid excessive reclaim overhead on large memory systems. Pages + may be non-reclaimable because: they are locked into memory, they + are anonymous pages for which no swap space exists, or they are anon + pages that are expensive to unmap [long anon_vma "related vma" list.]
Why do you select to default is NO ?
I think this is really improvement and no one of 64bit user hope turn off without NORECLAIM developer :)
- kosaki
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 10/19] No Reclaim LRU Infrastructure
Quoted 16 lines · KOSAKI Motohiro
Hi Rik
mm/Kconfig config NR_QUICK · line 205
Quoted 9 lines
mm/Kconfig +9
-0+config NORECLAIM + bool "Track non-reclaimable pages (EXPERIMENTAL; 64BIT only)" + depends on EXPERIMENTAL && 64BIT + help + Supports tracking of non-reclaimable pages off the [in]active lists + to avoid excessive reclaim overhead on large memory systems. Pages + may be non-reclaimable because: they are locked into memory, they + are anonymous pages for which no swap space exists, or they are anon + pages that are expensive to unmap [long anon_vma "related vma" list.]Why do you select to default is NO ?
I think this is really improvement and no one of 64bit user hope turn off without NORECLAIM developer :)
Hello, Kosaki-san:
This was my doing. I left the default == NO during development/experimemental stage so that one would have to take explicit action to enable this function. If the feature makes it into mainline and we decide that the default should be 'yes', that will be an easy change.
Thanks for looking at this,
Lee Schermerhorn
Re: [patch 10/19] No Reclaim LRU Infrastructure
Hi Lee-san
Quoted 14 lines
Quoted 5 lines
Quoted 5 lines
mm/Kconfig +5
-0+config NORECLAIM + bool "Track non-reclaimable pages (EXPERIMENTAL; 64BIT only)" + depends on EXPERIMENTAL && 64BIT + help + Supports tracking of non-reclaimable pages off the [in]active listsQuoted 8 lines
mm/Kconfig config NR_QUICK · line 205
Quoted 4 lines
mm/Kconfig +4
-0+ to avoid excessive reclaim overhead on large memory systems. Pages + may be non-reclaimable because: they are locked into memory, they + are anonymous pages for which no swap space exists, or they are anon + pages that are expensive to unmap [long anon_vma "related vma" list.]Why do you select to default is NO ?
I think this is really improvement and no one of 64bit user hope turn off without NORECLAIM developer :)
Quoted 5 lines
This was my doing. I left the default == NO during development/experimemental stage so that one would have to take explicit action to enable this function. If the feature makes it into mainline and we decide that the default should be 'yes', that will be an easy change.
Oh I see.
I will help testing too for it merges to mainline early.
thanks.
- kosaki
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 11/19 Non-reclaimable page statistics
In reply to Rik van RielV2 -> V3:
+ rebase to 23-mm1 atop RvR's split LRU series
V1 -> V2:
no changes
Report non-reclaimable pages per zone and system wide.
Note: may want to track/report some specific reasons for nonreclaimability for deciding when to splice the noreclaim lists back to the normal lru. That will be tricky, especially in shrink_active_list(), where we'd need someplace to save the per page reason for non-reclaimability until the pages are dumped back onto the noreclaim list from the pagevec.
Note: my tests indicate that NR_NORECLAIM and probably the other LRU stats aren't being maintained properly--especially with large amounts of mlocked memory and the mlock patch in this series installed. Can't be sure of this, as I don't know why the pages are on the noreclaim list. Needs further investigation.
mm/page_alloc.c +15 -1
@@ -1899,12 +1899,20 @@ void show_free_areas(void) } printk("Active_anon:%lu active_file:%lu inactive_anon%lu\n" - " inactive_file:%lu dirty:%lu writeback:%lu unstable:%lu\n" + " inactive_file:%lu" +//TODO: check/adjust line lengths +#ifdef CONFIG_NORECLAIM +" noreclaim:%lu" +#endif +" dirty:%lu writeback:%lu unstable:%lu\n" " free:%lu slab:%lu mapped:%lu pagetables:%lu bounce:%lu\n" ,global_page_state (NR_ACTIVE_ANON ),global_page_state (NR_ACTIVE_FILE ),global_page_state (NR_INACTIVE_ANON ),global_page_state (NR_INACTIVE_FILE ), +#ifdef CONFIG_NORECLAIM +global_page_state (NR_NORECLAIM ), +#endifglobal_page_state (NR_FILE_DIRTY ),global_page_state (NR_WRITEBACK ), global_page_state(NR_UNSTABLE_NFS),
@@ -1931,6 +1939,9 @@ void show_free_areas(void) " inactive_anon:%lukB" " active_file:%lukB" " inactive_file:%lukB" +#ifdef CONFIG_NORECLAIM + " noreclaim:%lukB" +#endif" present:%lukB" " pages_scanned:%lu" " all_unreclaimable? %s"
@@ -1944,6 +1955,9 @@ void show_free_areas(void)K (zone_page_state (zone,NR_INACTIVE_ANON )),K (zone_page_state (zone,NR_ACTIVE_FILE )),K (zone_page_state (zone,NR_INACTIVE_FILE )), +#ifdef CONFIG_NORECLAIM +K (zone_page_state (zone,NR_NORECLAIM )), +#endifK (zone->present_pages), zone->pages_scanned, (zone_is_all_unreclaimable (zone) ?"yes" :"no" )
mm/vmstat.c +3 -0
@@ -690,6 +690,9 @@ static const char * const vmstat_text[]"nr_active_anon" ,"nr_inactive_file" ,"nr_active_file" , +#ifdef CONFIG_NORECLAIM +"nr_noreclaim" , +#endif"nr_anon_pages" ,"nr_mapped" , "nr_file_pages",
drivers/base/node.c +6 -0
@@ -52,6 +52,9 @@ static ssize_t node_read_meminfo(struct "Node %d Inactive(anon): %8lu kB\n" "Node %d Active(file): %8lu kB\n" "Node %d Inactive(file): %8lu kB\n" +#ifdef CONFIG_NORECLAIM + "Node %d Noreclaim: %8lu kB\n" +#endif#ifdef CONFIG_HIGHMEM "Node %d HighTotal: %8lu kB\n" "Node %d HighFree: %8lu kB\n"
@@ -76,6 +79,9 @@ static ssize_t node_read_meminfo(struct nid,node_page_state (nid,NR_INACTIVE_ANON ), nid,node_page_state (nid,NR_ACTIVE_FILE ), nid,node_page_state (nid,NR_INACTIVE_FILE ), +#ifdef CONFIG_NORECLAIM + nid,node_page_state (nid,NR_NORECLAIM ), +#endif #ifdef CONFIG_HIGHMEM nid,K (i.totalhigh), nid, K(i.freehigh),
fs/proc/proc_misc.c +6 -0
@@ -162,6 +162,9 @@ static int meminfo_read_proc(char *page, "Inactive(anon): %8lu kB\n" "Active(file): %8lu kB\n" "Inactive(file): %8lu kB\n" +#ifdef CONFIG_NORECLAIM + "Noreclaim: %8lu kB\n" +#endif#ifdef CONFIG_HIGHMEM "HighTotal: %8lu kB\n" "HighFree: %8lu kB\n"
@@ -194,6 +197,9 @@ static int meminfo_read_proc(char *page,K (global_page_state (NR_INACTIVE_ANON )),K (global_page_state (NR_ACTIVE_FILE )),K (global_page_state (NR_INACTIVE_FILE )), +#ifdef CONFIG_NORECLAIM +K (global_page_state (NR_NORECLAIM )), +#endif #ifdef CONFIG_HIGHMEMK (i.totalhigh), K(i.freehigh),
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 12/19 scan noreclaim list for reclaimable pages
In reply to Rik van RielV2 -> V3:
+ rebase to 23-mm1 atop RvR's split LRU series
New in V2
This patch adds a function to scan individual or all zones' noreclaim lists and move any pages that have become reclaimable onto the respective zone's inactive list, where shrink_inactive_list() will deal with them.
This replaces the function to splice the entire noreclaim list onto the active list for rescan by shrink_active_list(). That method had problems with vmstat accounting and complicated '[__]isolate_lru_pages()'. Now, __isolate_lru_page() will never isolate a non-reclaimable page. The only time it should see one is when scanning nearby pages for lumpy reclaim.
TODO: This approach may still need some refinement.
E.g., put back to active list?
DEBUGGING ONLY: NOT FOR UPSTREAM MERGE
include/linux/swap.h +15 -0
@@ -7,6 +7,7 @@#include <linux/list.h> #include <linux/sched.h> #include <linux/memcontrol.h> +#include <linux/node.h> #include <asm/atomic.h> #include <asm/page.h>
@@ -215,12 +216,26 @@ static inline int zone_reclaim(struct zo#ifdef CONFIG_NORECLAIM extern int page_reclaimable (struct page *page,struct vm_area_struct *vma); +extern void scan_zone_noreclaim_pages (struct zone *); +extern void scan_all_zones_noreclaim_pages (void ); +extern unsigned long scan_noreclaim_pages; +extern int scan_noreclaim_handler (struct ctl_table *,int ,struct file *, +void __user *,size_t *,loff_t *); +extern int scan_noreclaim_register_node (struct node *node); +extern void scan_noreclaim_unregister_node (struct node *node);#else static inline int page_reclaimable (struct page *page,struct vm_area_struct *vma) {return 1 ; } +static inline void scan_zone_noreclaim_pages (struct zone *z) { } +static inline void scan_all_zones_noreclaim_pages (void ) { } +static inline int scan_noreclaim_register_node (struct node *node) +{ +return 0 ; +} +static inline void scan_noreclaim_unregister_node (struct node *node) { }#endif extern int kswapd_run (int nid);
mm/vmscan.c +141 -0
151 lines not on this page · raw message
kernel/sysctl.c +10 -0
@@ -1151,6 +1151,16 @@ static struct ctl_table vm_table[] = { .extra2 = &one, },#endif +#ifdef CONFIG_NORECLAIM + { + .ctl_name = CTL_UNNUMBERED, + .procname = "scan_noreclaim_pages", + .data = &scan_noreclaim_pages, + .maxlen = sizeof(scan_noreclaim_pages), + .mode = 0644, + .proc_handler = &scan_noreclaim_handler, + }, +#endif /* * NOTE: do not add new entries to this table unless you have read * Documentation/sysctl/ctl_unnumbered.txt
drivers/base/node.c +5 -0
@@ -13,6 +13,7 @@#include <linux/nodemask.h> #include <linux/cpu.h> #include <linux/device.h> +#include <linux/swap.h> static struct sysdev_class node_class = { .name ="node" ,
@@ -162,6 +163,8 @@ int register_node(struct node *node, intsysdev_create_file (&node->sysdev, &attr_meminfo);sysdev_create_file (&node->sysdev, &attr_numastat);sysdev_create_file (&node->sysdev, &attr_distance); + +scan_noreclaim_register_node (node); }return error; }
@@ -180,6 +183,8 @@ void unregister_node(struct node *node)sysdev_remove_file (&node->sysdev, &attr_numastat);sysdev_remove_file (&node->sysdev, &attr_distance); +scan_noreclaim_unregister_node (node); +sysdev_unregister (&node->sysdev); }
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 13/19 ramfs pages are non-reclaimable
In reply to Rik van RielV3 -> V4:
+ drivers/block/rd.c was replaced by brd.c in 24-rc4-mm1. Update patch to add brd_open() to mark mapping as nonreclaimable
V2 -> V3:
+ rebase to 23-mm1 atop RvR's split LRU series [no changes]
V1 -> V2:
+ add ramfs pages to this class of non-reclaimable pages by marking ramfs address_space [mapping] as non-reclaimble.
Christoph Lameter pointed out that ram disk pages also clutter the LRU lists. When vmscan finds them dirty and tries to clean them, the ram disk writeback function just redirties the page so that it goes back onto the active list. Round and round she goes...
Define new address_space flag [shares address_space flags member with mapping's gfp mask] to indicate that the address space contains all non-reclaimable pages. This will provide for efficient testing of ramdisk pages in page_reclaimable().
Also provide wrapper functions to set/test the noreclaim state to minimize #ifdefs in ramdisk driver and any other users of this facility.
Set the noreclaim state on address_space structures for new ramdisk inodes. Test the noreclaim state in page_reclaimable() to cull non-reclaimable pages.
Similarly, ramfs pages are non-reclaimable. Set the 'noreclaim' address_space flag for new ramfs inodes.
These changes depend on [CONFIG_]NORECLAIM.
include/linux/pagemap.h +22 -0
@@ -30,6 +30,28 @@ static inline void mapping_set_error(str } } +#ifdef CONFIG_NORECLAIM +#define AS_NORECLAIM (__GFP_BITS_SHIFT + 2)/* e.g., ramdisk, SHM_LOCK */ + +static inline void mapping_set_noreclaim (struct address_space *mapping) +{ +set_bit (AS_NORECLAIM , &mapping->flags); +} + +static inline int mapping_non_reclaimable (struct address_space *mapping) +{ +if (mapping && (mapping->flags &AS_NORECLAIM )) +return 1 ; +return 0 ; +} +#else +static inline void mapping_set_noreclaim (struct address_space *mapping) { } +static inline int mapping_non_reclaimable (struct address_space *mapping) +{ +return 0 ; +} +#endif +static inline gfp_t mapping_gfp_mask (struct address_space * mapping) {return (__force gfp_t )mapping->flags & __GFP_BITS_MASK;
mm/vmscan.c +4 -0
@@ -2258,6 +2258,7 @@ int zone_reclaim(struct zone *zone, gfp_* If !NULL, called from fault path. * * Reasons page might not be reclaimable: +* + page's mapping marked non-reclaimable * TODO - later patches * * TODO: specify locking assumptions
@@ -2267,6 +2268,9 @@ int page_reclaimable(struct page *page,VM_BUG_ON (PageNoreclaim (page)); +if (mapping_non_reclaimable (page_mapping (page))) +return 0 ; +/* TODO: test page [!]reclaimable conditions */ return 1 ;
fs/ramfs/inode.c +1 -0
@@ -61,6 +61,7 @@ struct inode *ramfs_get_inode(struct sup inode->i_mapping->a_ops = &ramfs_aops; inode->i_mapping->backing_dev_info = &ramfs_backing_dev_info;mapping_set_gfp_mask (inode->i_mapping,GFP_HIGHUSER ); +mapping_set_noreclaim (inode->i_mapping); inode->i_atime = inode->i_mtime = inode->i_ctime =CURRENT_TIME ;switch (mode &S_IFMT ) {default :
drivers/block/brd.c +13 -0
@@ -373,8 +373,21 @@ static int brd_ioctl(struct inode *inodereturn error; } +/* +* brd_open(): +* Just mark the mapping as containing non-reclaimable pages +*/ +static int brd_open (struct inode *inode,struct file *filp) +{ +struct address_space *mapping = inode->i_mapping; + +mapping_set_noreclaim (mapping); +return 0 ; +} +static struct block_device_operations brd_fops = { .owner =THIS_MODULE , + .open = brd_open, .ioctl = brd_ioctl, #ifdef CONFIG_BLK_DEV_XIP .direct_access = brd_direct_access,
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 14/19 SHM_LOCKED pages are nonreclaimable
In reply to Rik van RielV2 -> V3:
+ rebase to 23-mm1 atop RvR's split LRU series.
+ Use scan_mapping_noreclaim_page() on unlock. See below.
V1 -> V2:
+ modify to use reworked 'scan_all_zones_noreclaim_pages()' See 'TODO' below - still pending.
While working with Nick Piggin's mlock patches, I noticed that shmem segments locked via shmctl(SHM_LOCKED) were not being handled. SHM_LOCKed pages work like ramdisk pages--the writeback function just redirties the page so that it can't be reclaimed. Deal with these using the same approach as for ram disk pages.
Use the AS_NORECLAIM flag to mark address_space of SHM_LOCKed shared memory regions as non-reclaimable. Then these pages will be culled off the normal LRU lists during vmscan.
Add new wrapper function to clear the mapping's noreclaim state when/if shared memory segment is munlocked.
Add 'scan_mapping_noreclaim_page()' to mm/vmscan.c to scan all pages in the shmem segment's mapping [struct address_space] for reclaimability now that they're no longer locked. If so, move them to the appropriate zone lru list.
Changes depend on [CONFIG_]NORECLAIM.
mm/shmem.c +3 -0
@@ -1468,10 +1468,13 @@ int shmem_lock(struct file *file, int loif (!user_shm_lock (inode->i_size, user)) goto out_nomem; info->flags |=VM_LOCKED ; +mapping_set_noreclaim (file->f_mapping); }if (!lock && (info->flags &VM_LOCKED ) && user) {user_shm_unlock (inode->i_size, user); info->flags &= ~VM_LOCKED ; +mapping_clear_noreclaim (file->f_mapping); +scan_mapping_noreclaim_pages (file->f_mapping); } retval =0 ; out_nomem:
include/linux/pagemap.h +8 -2
@@ -38,14 +38,20 @@ static inline void mapping_set_noreclaim set_bit(AS_NORECLAIM, &mapping->flags); } +static inline void mapping_clear_noreclaim (struct address_space *mapping) +{ +clear_bit (AS_NORECLAIM , &mapping->flags); +} +static inline int mapping_non_reclaimable (struct address_space *mapping) { -if (mapping && (mapping->flags &AS_NORECLAIM )) -return 1 ; +if (mapping) +return test_bit (AS_NORECLAIM , &mapping->flags);return 0 ; }#else static inline void mapping_set_noreclaim (struct address_space *mapping) { } +static inline void mapping_clear_noreclaim (struct address_space *mapping) { }static inline int mapping_non_reclaimable (struct address_space *mapping) {return 0 ;
mm/vmscan.c +84 -17
130 lines not on this page · raw message
include/linux/swap.h +4 -0
@@ -218,6 +218,7 @@ static inline int zone_reclaim(struct zoextern int page_reclaimable (struct page *page,struct vm_area_struct *vma);extern void scan_zone_noreclaim_pages (struct zone *);extern void scan_all_zones_noreclaim_pages (void ); +extern void scan_mapping_noreclaim_pages (struct address_space *);extern unsigned long scan_noreclaim_pages;extern int scan_noreclaim_handler (struct ctl_table *,int ,struct file *,void __user *,size_t *,loff_t *);
@@ -231,6 +232,9 @@ static inline int page_reclaimable(struc }static inline void scan_zone_noreclaim_pages (struct zone *z) { }static inline void scan_all_zones_noreclaim_pages (void ) { } +static inline void scan_mapping_noreclaim_pages (struct address_space *mapping) +{ +}static inline int scan_noreclaim_register_node (struct node *node) {return 0 ;
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 15/19 non-reclaimable mlocked pages
In reply to Rik van RielV2 -> V3:
+ rebase to 23-mm1 atop RvR's split lru series
+ fix page flags macros for *PageMlocked() when not configured.
+ ensure lru_add_drain_all() runs on all cpus when NORECLIM_MLOCK configured. Was just for NUMA.
V1 -> V2:
+ moved this patch [and related patches] up to right after ramdisk/ramfs and SHM_LOCKed patches.
+ add [back] missing put_page() in putback_lru_page(). This solved page leakage as seen by stats in previous version.
+ fix up munlock_vma_page() to isolate page from lru before calling try_to_unlock(). Think I detected a race here.
+ use TestClearPageMlock() on old page in migrate.c's migrate_page_copy() to clean up old page.
+ live dangerously: remove TestSetPageLocked() in is_mlocked_vma()--should only be called on new pages in the fault path--iff we chose to cull there [later patch].
+ Add PG_mlocked to free_pages_check() etc to detect mlock state mismanagement.
NOTE: temporarily [???] commented out--tripping over it under load. Why?
Rework of a patch by Nick Piggin -- part 1 of 2.
This patch:
1) defines the [CONFIG_]NORECLAIM_MLOCK sub-option and the stub version of the mlock/noreclaim APIs when it's not configured. Depends on [CONFIG_]NORECLAIM.
2) add yet another page flag--PG_mlocked--to indicate that the page is locked for efficient testing in vmscan and, optionally, fault path. This allows early culling of nonreclaimable pages, preventing them from getting to page_referenced()/try_to_unmap(). Also allows separate accounting of mlock'd pages, as Nick's original patch did.
Uses a bit available only to 64-bit systems.
Note: Nick's original mlock patch used a PG_mlocked flag. I had removed this in favor of the PG_noreclaim flag + an mlock_count [new page struct member]. I restored the PG_mlocked flag to eliminate the new count field.
3) add the mlock/noreclaim infrastructure to mm/mlock.c, with internal APIs in mm/internal.h. This is a rework of Nick's original patch to these files, taking into account that mlocked pages are now kept on noreclaim LRU list.
4) update vmscan.c:page_reclaimable() to check PageMlocked() and, if vma passed in, the vm_flags. Note that the vma will only be passed in for new pages in the fault path; and then only if the "cull nonreclaimable pages in fault path" patch is included.
5) add try_to_unlock() to rmap.c to walk a page's rmap and ClearPageMlocked() if no other vmas have it mlocked. Reuses as much of try_to_unmap() as possible. This effectively replaces the use of one of the lru list links as an mlock count. If this mechanism let's pages in mlocked vmas leak through w/o PG_mlocked set [I don't know that it does], we should catch them later in try_to_unmap(). One hopes this will be rare, as it will be relatively expensive.
mm/internal.h and mm/mlock.c changes:
Originally Signed-off-by: Nick Piggin <[email protected]>
mm/Kconfig +14 -0
@@ -203,3 +203,17 @@ config NORECLAIM may be non-reclaimable because: they are locked into memory, they are anonymous pages for which no swap space exists, or they are anon pages that are expensive to unmap [long anon_vma "related vma" list.] + +config NORECLAIM_MLOCK + bool "Exclude mlock'ed pages from reclaim" + depends on NORECLAIM + help + Treats mlock'ed pages as no-reclaimable. Removing these pages from + the LRU [in]active lists avoids the overhead of attempting to reclaim + them. Pages marked non-reclaimable for this reason will become + reclaimable again when the last mlock is removed. + when no swap space exists. Removing these pages from the LRU lists + avoids the overhead of attempting to reclaim them. Pages marked + non-reclaimable for this reason will become reclaimable again when/if + sufficient swap space is added to the system. +
mm/internal.h +58 -0
64 lines not on this page · raw message
mm/mlock.c +210 -13
263 lines not on this page · raw message
mm/vmscan.c +46 -2
68 lines not on this page · raw message
include/linux/page-flags.h +21 -2
@@ -110,6 +110,7 @@#define PG_uncached 31/* Page has been mapped as uncached */ #define PG_noreclaim 30/* Page is "non-reclaimable" */ +#define PG_mlocked 29/* Page is vma mlocked */ #endif /*
@@ -163,6 +164,7 @@ static inline void SetPageUptodate(struc#define SetPageActive (page) set_bit(PG_active, &(page)->flags)#define ClearPageActive (page) clear_bit(PG_active, &(page)->flags)#define __ClearPageActive (page) __clear_bit(PG_active, &(page)->flags) +#define TestSetPageActive (page) test_and_set_bit(PG_active, &(page)->flags)#define TestClearPageActive (page) test_and_clear_bit(PG_active, &(page)->flags)#define PageSlab (page) test_bit(PG_slab, &(page)->flags)
@@ -270,8 +272,17 @@ static inline void __ClearPageTail(struc#define SetPageNoreclaim (page) set_bit(PG_noreclaim, &(page)->flags)#define ClearPageNoreclaim (page) clear_bit(PG_noreclaim, &(page)->flags)#define __ClearPageNoreclaim (page) __clear_bit(PG_noreclaim, &(page)->flags) -#define TestClearPageNoreclaim (page) test_and_clear_bit(PG_noreclaim, \ - &(page)->flags) +#define TestClearPageNoreclaim (page) \ + test_and_clear_bit(PG_noreclaim, &(page)->flags) +#ifdef CONFIG_NORECLAIM_MLOCK +#define PageMlocked (page) test_bit(PG_mlocked, &(page)->flags) +#define SetPageMlocked (page) set_bit(PG_mlocked, &(page)->flags) +#define ClearPageMlocked (page) clear_bit(PG_mlocked, &(page)->flags) +#define __ClearPageMlocked (page) __clear_bit(PG_mlocked, &(page)->flags) +#define TestSetPageMlocked (page) test_and_set_bit(PG_mlocked, &(page)->flags) +#define TestClearPageMlocked (page) \ + test_and_clear_bit(PG_mlocked, &(page)->flags) +#endif #else #define PageNoreclaim (page) 0#define SetPageNoreclaim (page)
@@ -279,6 +290,14 @@ static inline void __ClearPageTail(struc#define __ClearPageNoreclaim (page)#define TestClearPageNoreclaim (page) 0#endif +#ifndef CONFIG_NORECLAIM_MLOCK +#define PageMlocked (page) 0 +#define SetPageMlocked (page) +#define ClearPageMlocked (page) +#define __ClearPageMlocked (page) +#define TestSetPageMlocked (page) 0 +#define TestClearPageMlocked (page) 0 +#endif #define PageUncached (page) test_bit(PG_uncached, &(page)->flags)#define SetPageUncached (page) set_bit(PG_uncached, &(page)->flags)
include/linux/rmap.h +12 -0
@@ -109,6 +109,17 @@ unsigned long page_address_in_vma(struct*/ int page_mkclean (struct page *); +#ifdef CONFIG_NORECLAIM_MLOCK +/* +* called in munlock()/munmap() path to check for other vmas holding +* the page mlocked. +*/ +int try_to_unlock (struct page *); +#define TRY_TO_UNLOCK 1 +#else +#define TRY_TO_UNLOCK 0/* for compiler -- dead code elimination */ +#endif +#else /* !CONFIG_MMU */ #define anon_vma_init () do {} while (0)
@@ -132,5 +143,6 @@ static inline int page_mkclean(struct pa#define SWAP_SUCCESS 0#define SWAP_AGAIN 1#define SWAP_FAIL 2 +#define SWAP_MLOCK 3#endif /* _LINUX_RMAP_H */
mm/rmap.c +135 -25
270 lines not on this page · raw message
mm/migrate.c +3 -0
@@ -366,6 +366,9 @@ static void migrate_page_copy(struct pagset_page_dirty (newpage); } +if (TestClearPageMlocked (page)) +SetPageMlocked (newpage); +#ifdef CONFIG_SWAP ClearPageSwapCache (page);#endif
mm/page_alloc.c +9 -1
@@ -257,6 +257,7 @@ static void bad_page(struct page *page)1 << PG_swapcache |1 << PG_writeback |1 << PG_swapbacked | +1 << PG_mlocked | 1 << PG_buddy );set_page_count (page,0 );reset_page_mapcount (page);
@@ -488,6 +489,9 @@ static inline int free_pages_check(struc#ifdef CONFIG_NORECLAIM 1 << PG_noreclaim |#endif +// TODO: always trip this under heavy workloads. +// Why isn't this being cleared on last unmap/unlock? +// 1 << PG_mlocked | 1 << PG_buddy ))))bad_page (page);if (PageDirty (page))
@@ -644,6 +648,8 @@ static int prep_new_page(struct page *pa 1 << PG_writeback | 1 << PG_reserved | 1 << PG_swapbacked | +//TODO: why hitting this? +// 1 << PG_mlocked | 1 << PG_buddy ))))bad_page (page);
@@ -656,7 +662,9 @@ static int prep_new_page(struct page *pa page->flags &= ~(1 << PG_uptodate |1 << PG_error |1 << PG_readahead |1 << PG_referenced |1 << PG_arch_1 | -1 << PG_owner_priv_1 |1 << PG_mappedtodisk); +1 << PG_owner_priv_1 |1 << PG_mappedtodisk | +//TODO take care of it here, for now. +1 << PG_mlocked );set_page_private (page,0 );set_page_refcounted (page);
mm/swap.c +1 -1
@@ -346,7 +346,7 @@ void lru_add_drain(void)put_cpu (); } -#ifdef CONFIG_NUMA +#if defined(CONFIG_NUMA ) || defined(CONFIG_NORECLAIM_MLOCK )static void lru_add_drain_per_cpu (struct work_struct *dummy) {lru_add_drain ();
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 16/19 mlock vma pages under mmap_sem held for read
In reply to Rik van RielV2 -> V3:
+ rebase to 23-mm1 atop RvR's split lru series [no change]
+ fix function return types [void -> int] to fix build when not configured.
New in V2.
We need to hold the mmap_sem for write to initiatate mlock()/munlock() because we may need to merge/split vmas. However, this can lead to very long lock hold times attempting to fault in a large memory region
to mlock it into memory. This can hold off other faults against the
mm [multithreaded tasks] and other scans of the mm, such as via /proc. To alleviate this, downgrade the mmap_sem to read mode during the population of the region for locking. This is especially the case if we need to reclaim memory to lock down the region. We [probably?] don't need to do this for unlocking as all of the pages should be resident--they're already mlocked.
Now, the caller's of the mlock functions [mlock_fixup() and mlock_vma_pages_range()] expect the mmap_sem to be returned in write mode. Changing all callers appears to be way too much effort at this point. So, restore write mode before returning. Note that this opens a window where the mmap list could change in a multithreaded process. So, at least for mlock_fixup(), where we could be called in a loop over multiple vmas, we check that a vma still exists at the start address and that vma still covers the page range [start,end). If not, we return an error, -EAGAIN, and let the caller deal with it.
Return -EAGAIN from mlock_vma_pages_range() function and mlock_fixup() if the vma at 'start' disappears or changes so that the page range [start,end) is no longer contained in the vma. Again, let the caller deal with it. Looks like only sys_remap_file_pages() [via mmap_region()] should actually care.
With this patch, I no longer see processes like ps(1) blocked for seconds or minutes at a time waiting for a large [multiple gigabyte] region to be locked down.
mm/mlock.c +56 -1
@@ -200,6 +200,37 @@ int __mlock_vma_pages_range(struct vm_ar return ret; } +/** +* mlock_vma_pages_range +* @vma - vm area to mlock into memory +* @start - start address in @vma of range to mlock, +* @end - end address in @vma of range +* +* Called with current->mm->mmap_sem held write locked. Downgrade to read +* for faulting in pages. This can take a looong time for large segments. +* +* We need to restore the mmap_sem to write locked because our callers' +* callers expect this. However, because the mmap could have changed +* [in a multi-threaded process], we need to recheck. +*/ +int mlock_vma_pages_range (struct vm_area_struct *vma, +unsigned long start,unsigned long end) +{ +struct mm_struct *mm = vma->vm_mm; + +downgrade_write (&mm->mmap_sem); +__mlock_vma_pages_range (vma, start, end,1 ); + +up_read (&mm->mmap_sem); +/* vma can change or disappear */ +down_write (&mm->mmap_sem); + vma =find_vma (mm, start); +/* non-NULL vma must contain @start, but need to check @end */ +if (!vma || end > vma->vm_end) +return -EAGAIN ; +return 0 ; +} +#else /* CONFIG_NORECLAIM_MLOCK */ /*
@@ -266,14 +297,38 @@ success: mm->locked_vm += nr_pages;/* -* vm_flags is protected by the mmap_sem held in write mode. +* vm_flags is protected by the mmap_sem held for write. * It's okay if try_to_unmap_one unmaps a page just after we * set VM_LOCKED, __mlock_vma_pages_range will bring it back. */ vma->vm_flags = newflags; +/* +* mmap_sem is currently held for write. If we're locking pages, +* downgrade the write lock to a read lock so that other faults, +* mmap scans, ... while we fault in all pages. +*/ +if (lock) +downgrade_write (&mm->mmap_sem); +__mlock_vma_pages_range (vma, start, end, lock); +if (lock) { +/* +* Need to reacquire mmap sem in write mode, as our callers +* expect this. We have no support for atomically upgrading +* a sem to write, so we need to check for changes while sem +* is unlocked. +*/ +up_read (&mm->mmap_sem); +/* vma can change or disappear */ +down_write (&mm->mmap_sem); + *prev =find_vma (mm, start); +/* non-NULL *prev must contain @start, but need to check @end */ +if (!(*prev) || end > (*prev)->vm_end) + ret = -EAGAIN ; + } + out:if (ret == -ENOMEM ) ret = -EAGAIN ;
mm/internal.h +8 -11
@@ -61,24 +61,21 @@ extern int __mlock_vma_pages_range(struc/* * mlock all pages in this vma range. For mmap()/mremap()/... */ -static inline void mlock_vma_pages_range (struct vm_area_struct *vma, -unsigned long start,unsigned long end) -{ -__mlock_vma_pages_range (vma, start, end,1 ); -} +extern int mlock_vma_pages_range (struct vm_area_struct *vma, +unsigned long start,unsigned long end);/* * munlock range of pages. For munmap() and exit(). * Always called to operate on a full vma that is being unmapped. */ -static inline void munlock_vma_pages_range (struct vm_area_struct *vma, +static inline int munlock_vma_pages_range (struct vm_area_struct *vma,unsigned long start,unsigned long end) {// TODO: verify my assumption. Should we just drop the start/end args? VM_BUG_ON (start != vma->vm_start || end != vma->vm_end); vma->vm_flags &= ~VM_LOCKED ;/* try_to_unlock() needs this */ -__mlock_vma_pages_range (vma, start, end,0 ); +return __mlock_vma_pages_range (vma, start, end,0 ); }extern void clear_page_mlock (struct page *page);
@@ -90,10 +87,10 @@ static inline int is_mlocked_vma(struct }static inline void clear_page_mlock (struct page *page) { }static inline void mlock_vma_page (struct page *page) { } -static inline void mlock_vma_pages_range (struct vm_area_struct *vma, -unsigned long start,unsigned long end) { } -static inline void munlock_vma_pages_range (struct vm_area_struct *vma, -unsigned long start,unsigned long end) { } +static inline int mlock_vma_pages_range (struct vm_area_struct *vma, +unsigned long start,unsigned long end) {return 0 ; } +static inline int munlock_vma_pages_range (struct vm_area_struct *vma, +unsigned long start,unsigned long end) {return 0 ; }#endif /* CONFIG_NORECLAIM_MLOCK */
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 17/19 handle mlocked pages during map/unmap and truncate
In reply to Rik van RielV2 -> V3:
+ rebase to 23-mm1 atop RvR's split lru series [no changes]
V1 -> V2:
+ modified mmap.c:mmap_region() to return error if mlock_vma_pages_range() does. This can only occur if the vma gets removed/changed while
we're switching mmap_sem lock modes. Most callers don't care, but
sys_remap_file_pages() appears to.
Rework of Nick Piggins's "mm: move mlocked pages off the LRU" patch -- part 2 0f 2.
Remove mlocked pages from the LRU using "NoReclaim infrastructure" during mmap()/mremap(). Try to move back to normal LRU lists on munmap() when last locked mapping removed. Removed PageMlocked() status when page truncated from file.
Originally Signed-off-by: Nick Piggin <[email protected]>
mm/mmap.c +37 -5
@@ -32,6 +32,8 @@#include <asm/tlb.h> #include <asm/mmu_context.h> +#include "internal.h" +#ifndef arch_mmap_check#define arch_mmap_check (addr, len, flags) (0)#endif
@@ -1201,9 +1203,13 @@ out:vm_stat_account (mm, vm_flags, file, len >>PAGE_SHIFT );if (vm_flags &VM_LOCKED ) { mm->locked_vm += len >>PAGE_SHIFT ; -make_pages_present (addr, addr + len); - } -if ((flags &MAP_POPULATE ) && !(flags &MAP_NONBLOCK )) +/* +* makes pages present; downgrades, drops, requires mmap_sem +*/ + error =mlock_vma_pages_range (vma, addr, addr + len); +if (error) +return error;/* vma gone! */ + }else if ((flags &MAP_POPULATE ) && !(flags &MAP_NONBLOCK ))make_pages_present (addr, addr + len);return addr;
@@ -1886,6 +1892,19 @@ int do_munmap(struct mm_struct *mm, unsi vma = prev? prev->vm_next: mm->mmap;/* +* unlock any mlock()ed ranges before detaching vmas +*/ +if (mm->locked_vm) { +struct vm_area_struct *tmp = vma; +while (tmp && tmp->vm_start < end) { +if (tmp->vm_flags &VM_LOCKED ) +munlock_vma_pages_range (tmp, + tmp->vm_start, tmp->vm_end); + tmp = tmp->vm_next; + } + } + +/* * Remove the vma's, and unmap the actual pages */ detach_vmas_to_be_unmapped (mm, vma, prev, end);
@@ -2021,7 +2040,7 @@ out: mm->total_vm += len >>PAGE_SHIFT ;if (flags &VM_LOCKED ) { mm->locked_vm += len >>PAGE_SHIFT ; -make_pages_present (addr, addr + len); +mlock_vma_pages_range (vma, addr, addr + len); }return addr; }
@@ -2032,13 +2051,26 @@ EXPORT_SYMBOL(do_brk);void exit_mmap (struct mm_struct *mm) {struct mmu_gather *tlb; -struct vm_area_struct *vma = mm->mmap; +struct vm_area_struct *vma;unsigned long nr_accounted =0 ;unsigned long end;/* mm's last user has gone, and its about to be pulled down */ arch_exit_mmap (mm); +if (mm->locked_vm) { + vma = mm->mmap; +while (vma) { +if (vma->vm_flags &VM_LOCKED ) +munlock_vma_pages_range (vma, + vma->vm_start, vma->vm_end); + vma = vma->vm_next; + } + } + + vma = mm->mmap; + +lru_add_drain ();flush_cache_mm (mm); tlb =tlb_gather_mmu (mm,1 );
mm/mremap.c +5 -3
@@ -23,6 +23,8 @@#include <asm/cacheflush.h> #include <asm/tlbflush.h> +#include "internal.h" +static pmd_t *get_old_pmd (struct mm_struct *mm,unsigned long addr) {pgd_t *pgd;
@@ -232,8 +234,8 @@ static unsigned long move_vma(struct vm_if (vm_flags &VM_LOCKED ) { mm->locked_vm += new_len >>PAGE_SHIFT ;if (new_len > old_len) -make_pages_present (new_addr + old_len, - new_addr + new_len); +mlock_vma_pages_range (vma, new_addr + old_len, + new_addr + new_len); }return new_addr;
@@ -373,7 +375,7 @@ unsigned long do_mremap(unsigned long advm_stat_account (mm, vma->vm_flags, vma->vm_file, pages);if (vma->vm_flags &VM_LOCKED ) { mm->locked_vm += pages; -make_pages_present (addr + old_len, +mlock_vma_pages_range (vma, addr + old_len, addr + new_len); } ret = addr;
mm/vmscan.c +4 -0
@@ -540,6 +540,10 @@ static unsigned long shrink_page_list(st goto activate_locked;case SWAP_AGAIN : goto keep_locked; +case SWAP_MLOCK : +ClearPageActive (page); +SetPageNoreclaim (page); + goto keep_locked;/* to noreclaim list */ case SWAP_SUCCESS : ;/* try to free the page below */ }
mm/filemap.c +9 -1
@@ -2525,8 +2525,16 @@ generic_file_direct_IO(int rw, struct kiif (rw ==WRITE ) { write_len =iov_length (iov, nr_segs); end = (offset + write_len -1 ) >>PAGE_CACHE_SHIFT ; -if (mapping_mapped (mapping)) +if (mapping_mapped (mapping)) { +/* +* Calling unmap_mapping_range like this is wrong, +* because it can lead to mlocked pages being +* discarded (this is true even before the Noreclaim +* mlock work). direct-IO vs pagecache is a load of +* junk anyway, so who cares. +*/ unmap_mapping_range (mapping, offset, write_len,0 ); + } } retval =filemap_write_and_wait (mapping);
mm/truncate.c +4 -0
@@ -18,6 +18,7 @@#include <linux/task_io_accounting_ops.h> #include <linux/buffer_head.h> /* grr. try_to_release_page, do_invalidatepage */ +#include "internal.h" /**
@@ -104,6 +105,7 @@ truncate_complete_page(struct address_spcancel_dirty_page (page,PAGE_CACHE_SIZE );remove_from_page_cache (page); +clear_page_mlock (page);ClearPageUptodate (page);ClearPageMappedToDisk (page);page_cache_release (page);/* pagecache ref */
@@ -128,6 +130,7 @@ invalidate_complete_page(struct address_if (PagePrivate (page) && !try_to_release_page (page,0 ))return 0 ; +clear_page_mlock (page); ret =remove_mapping (mapping, page);return ret;
@@ -354,6 +357,7 @@ invalidate_complete_page2(struct addressif (PageDirty (page)) goto failed; +clear_page_mlock (page);BUG_ON (PagePrivate (page));__remove_from_page_cache (page);write_unlock_irq (&mapping->tree_lock);
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 18/19 account mlocked pages
In reply to Rik van RielV2 -> V3:
+ rebase to 23-mm1 atop RvR's split lru series
+ fix definitions of NR_MLOCK to fix build errors when not configured.
V1 -> V2:
+ new in V2 -- pulled in & reworked from Nick's previous series
From: Nick Piggin <[email protected]>
To: Linux Memory Management <[email protected]>
Cc: Nick Piggin <[email protected]>, Andrew Morton <[email protected]>
Subject: [patch 4/4] mm: account mlocked pages
Date: Mon, 12 Mar 2007 07:39:14 +0100 (CET)
Add NR_MLOCK zone page state, which provides a (conservative) count of mlocked pages (actually, the number of mlocked pages moved off the LRU).
Reworked by lts to fit in with the modified mlock page support in the Reclaim Scalability series. I don't know whether we'll want to keep these stats in the long run, but during testing of this series, I find them useful.
drivers/base/node.c +6 -0
@@ -55,6 +55,9 @@ static ssize_t node_read_meminfo(struct "Node %d Inactive(file): %8lu kB\n" #ifdef CONFIG_NORECLAIM "Node %d Noreclaim: %8lu kB\n" +#ifdef CONFIG_NORECLAIM_MLOCK + "Node %d Mlocked: %8lu kB\n" +#endif #endif#ifdef CONFIG_HIGHMEM "Node %d HighTotal: %8lu kB\n"
@@ -82,6 +85,9 @@ static ssize_t node_read_meminfo(struct nid, node_page_state(nid, NR_INACTIVE_FILE),#ifdef CONFIG_NORECLAIM nid, node_page_state(nid, NR_NORECLAIM), +#ifdef CONFIG_NORECLAIM_MLOCK + nid, K(node_page_state(nid, NR_MLOCK)), +#endif #endif #ifdef CONFIG_HIGHMEM nid, K(i.totalhigh),
fs/proc/proc_misc.c +6 -0
@@ -164,6 +164,9 @@ static int meminfo_read_proc(char *page, "Inactive(file): %8lu kB\n" #ifdef CONFIG_NORECLAIM "Noreclaim: %8lu kB\n" +#ifdef CONFIG_NORECLAIM_MLOCK + "Mlocked: %8lu kB\n" +#endif #endif#ifdef CONFIG_HIGHMEM "HighTotal: %8lu kB\n"
@@ -199,6 +202,9 @@ static int meminfo_read_proc(char *page, K(global_page_state(NR_INACTIVE_FILE)),#ifdef CONFIG_NORECLAIM K(global_page_state(NR_NORECLAIM)), +#ifdef CONFIG_NORECLAIM_MLOCK + K(global_page_state(NR_MLOCK)), +#endif #endif #ifdef CONFIG_HIGHMEM K(i.totalhigh),
include/linux/mmzone.h +5 -1
@@ -86,8 +86,12 @@ enum zone_stat_item { NR_ACTIVE_FILE, /* " " " " " */#ifdef CONFIG_NORECLAIM NR_NORECLAIM, /* " " " " " */ +#ifdef CONFIG_NORECLAIM_MLOCK + NR_MLOCK, /* mlock()ed pages found and moved off LRU */ +#endif #else -NR_NORECLAIM =NR_ACTIVE_FILE ,/* avoid compiler errors in dead code */ +NR_NORECLAIM =NR_ACTIVE_FILE ,/* avoid compiler errors in dead code */ +NR_MLOCK =NR_ACTIVE_FILE ,/* avoid compiler errors... */ #endifNR_ANON_PAGES ,/* Mapped anonymous pages */ NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
mm/mlock.c +27 -11
@@ -60,11 +60,11 @@ void clear_page_mlock(struct page *page) {BUG_ON (!PageLocked (page)); -if (likely (!PageMlocked (page))) -return ; -ClearPageMlocked (page); -if (!isolate_lru_page (page)) -putback_lru_page (page); +if (unlikely (TestClearPageMlocked (page))) { +dec_zone_page_state (page,NR_MLOCK ); +if (!isolate_lru_page (page)) +putback_lru_page (page); + } }/*
@@ -75,8 +75,11 @@ void mlock_vma_page(struct page *page) {BUG_ON (!PageLocked (page)); -if (!TestSetPageMlocked (page) && !isolate_lru_page (page)) +if (!TestSetPageMlocked (page)) { +inc_zone_page_state (page,NR_MLOCK ); +if (!isolate_lru_page (page))putback_lru_page (page); + } }/*
@@ -98,10 +101,22 @@ static void munlock_vma_page(struct page {BUG_ON (!PageLocked (page)); -if (TestClearPageMlocked (page) && !isolate_lru_page (page)) { -if (try_to_unlock (page) ==SWAP_MLOCK ) -SetPageMlocked (page);/* still VM_LOCKED */ -putback_lru_page (page); +if (TestClearPageMlocked (page)) { +dec_zone_page_state (page,NR_MLOCK ); +if (!isolate_lru_page (page)) { +if (try_to_unlock (page) ==SWAP_MLOCK ) { +SetPageMlocked (page);/* still VM_LOCKED */ +inc_zone_page_state (page,NR_MLOCK ); + } +putback_lru_page (page); + } +/* +* Else we lost the race. let try_to_unmap() deal with it. +* At least we get the page state and mlock stats right. +* However, page is still on the noreclaim list. We'll fix +* that up when the page is eventually freed or we scan the +* noreclaim list. +*/ } }
@@ -118,7 +133,8 @@ int is_mlocked_vma(struct vm_area_structif (likely (!(vma->vm_flags &VM_LOCKED )))return 0 ; -SetPageMlocked (page); +if (!TestSetPageMlocked (page)) +inc_zone_page_state (page,NR_MLOCK );return 1 ; }
mm/migrate.c +8 -1
@@ -366,8 +366,15 @@ static void migrate_page_copy(struct pagset_page_dirty (newpage); } -if (TestClearPageMlocked (page)) +if (TestClearPageMlocked (page)) { +unsigned long flags; + +local_irq_save (flags); +__dec_zone_page_state (page,NR_MLOCK );SetPageMlocked (newpage); +__inc_zone_page_state (newpage,NR_MLOCK ); +local_irq_restore (flags); + }#ifdef CONFIG_SWAP ClearPageSwapCache (page);
mm/vmstat.c +3 -0
@@ -693,6 +693,9 @@ static const char * const vmstat_text[]#ifdef CONFIG_NORECLAIM "nr_noreclaim",#endif +#ifdef CONFIG_NORECLAIM_MLOCK +"nr_mlock" , +#endif"nr_anon_pages" ,"nr_mapped" , "nr_file_pages",
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Re: [patch 18/19] account mlocked pages
* Rik van Riel <[email protected]> [2008-01-08 15:59:57]:
The following patch is required to compile the code with CONFIG_NORECLAIM enabled and CONFIG_NORECLAIM_MLOCK disabled.
include/linux/mmzone.h +2 -0
@@ -88,6 +88,8 @@ enum zone_stat_item { NR_NORECLAIM, /* " " " " " */#ifdef CONFIG_NORECLAIM_MLOCK NR_MLOCK ,/* mlock()ed pages found and moved off LRU */ +#else +NR_MLOCK =NR_ACTIVE_FILE ,/* avoid compiler errors... */ #endif #else NR_NORECLAIM=NR_ACTIVE_FILE, /* avoid compiler errors in dead code */
Signature · 4 lines
Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL
Re: [patch 18/19] account mlocked pages
Quoted 4 lines · On Fri, 11 Jan 2008 18:21:09 +0530 Balbir Singh <[email protected]>…
* Rik van Riel <[email protected]> [2008-01-08 15:59:57]:
The following patch is required to compile the code with
CONFIG_NORECLAIMenabled andCONFIG_NORECLAIM_MLOCKdisabled.
I have untangled the #ifdefs to make things compile with all combinations of config settings. Thanks for pointing out this problem.
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
PATCH 19/19 cull non-reclaimable anon pages from the LRU at fault time
In reply to Rik van RielV2 -> V3:
+ rebase to 23-mm1 atop RvR's split lru series.
V1 -> V2:
+ no changes
Optional part of "noreclaim infrastructure"
In the fault paths that install new anonymous pages, check whether the page is reclaimable or not using lru_cache_add_active_or_noreclaim(). If the page is reclaimable, just add it to the active lru list [via the pagevec cache], else add it to the noreclaim list.
This "proactive" culling in the fault path mimics the handling of mlocked pages in Nick Piggin's series to keep mlocked pages off the lru lists.
Notes:
1) This patch is optional--e.g., if one is concerned about the additional test in the fault path. We can defer the moving of nonreclaimable pages until when vmscan [shrink_*_list()] encounters them. Vmscan will only need to handle such pages once.
2) I moved the call to page_add_new_anon_rmap() to before the test for page_reclaimable() and thus before the calls to lru_cache_add_{active|noreclaim}(), so that page_reclaimable() could recognize the page as anon, thus obviating, I think, the vma arg to page_reclaimable() for this purpose. Still needed for culling mlocked pages in fault path [later patch].
TBD: I think this reordering is OK, but the previous order may
have existed to close some obscure race?
3) With this and other patches above installed, any anon pages created before swap is added--e.g., init's anonymous memory-- will be declared non-reclaimable and placed on the noreclaim LRU list. Need to add mechanism to bring such pages back when swap becomes available.
mm/memory.c +5 -5
@@ -1665,7 +1665,7 @@ gotten:set_pte_at (mm, address, page_table, entry);update_mmu_cache (vma, address, entry);SetPageSwapBacked (new_page); -lru_cache_add_active_anon (new_page); +lru_cache_add_active_or_noreclaim (new_page, vma);page_add_new_anon_rmap (new_page, vma, address);/* Free the old page.. */
@@ -2133,7 +2133,7 @@ static int do_anonymous_page(struct mm_s goto release;inc_mm_counter (mm, anon_rss);SetPageSwapBacked (page); -lru_cache_add_active_anon (page); +lru_cache_add_active_or_noreclaim (page, vma);page_add_new_anon_rmap (page, vma, address);set_pte_at (mm, address, page_table, entry);
@@ -2285,10 +2285,10 @@ static int __do_fault(struct mm_struct * entry =maybe_mkwrite (pte_mkdirty (entry), vma);set_pte_at (mm, address, page_table, entry);if (anon) { -inc_mm_counter (mm, anon_rss); +inc_mm_counter (mm, anon_rss);SetPageSwapBacked (page); -lru_cache_add_active_anon (page); -page_add_new_anon_rmap (page, vma, address); +lru_cache_add_active_or_noreclaim (page, vma); +page_add_new_anon_rmap (page, vma, address); }else {inc_mm_counter (mm, file_rss);page_add_file_rmap (page);
mm/swap_state.c +4 -1
@@ -300,7 +300,10 @@ struct page *read_swap_cache_async(swp_e/* * Initiate read into locked page and return. */ -lru_cache_add_anon (new_page); +if (!page_reclaimable (new_page, vma)) +lru_cache_add_noreclaim (new_page); +else +lru_cache_add_anon (new_page);swap_readpage (NULL , new_page);return new_page; }
Signature · 7 lines
All Rights Reversed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Quoted 6 lines · Rik van Riel
On large memory systems, the VM can spend way too much time scanning through pages that it cannot (or should not) evict from memory. Not only does it use up CPU time, but it also provokes lock contention and can leave large systems under memory presure in a catatonic state.
Against 2.6.24-rc6-mm1
Hi Rik,
How much trouble am I asking for if I were to try to get your patchset to fly on a fairly recent "stable" kernel (e.g. 2.6.22.15)? If workable, is such an effort before it's time relative to your TODO?
I see that you have an old port to a FC7-based 2.6.21 here:
http://people.redhat.com/riel/vmsplit/
Also, do you have a public git repo that you regularly publish to for this patchset? If not a git repo do you put the raw patchset on some http/ftp server?
thanks,
Mike
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Quoted 3 lines · On Wed, 9 Jan 2008 23:39:02 -0500 "Mike Snitzer" <[email protected]> wrote:
How much trouble am I asking for if I were to try to get your patchset to fly on a fairly recent "stable" kernel (e.g. 2.6.22.15)? If workable, is such an effort before it's time relative to your TODO?
Quite a bit :)
The -mm kernel has the memory controller code, which means the mm/ directory is fairly different. My patch set sits on top of that.
Chances are that once the -mm kernel goes upstream (in 2.6.25-rc1), I can start building on top of that.
OTOH, maybe I could get my patch series onto a recent 2.6.23.X with minimal chainsaw effort.
Quoted 6 lines
I see that you have an old port to a FC7-based 2.6.21 here:
http://people.redhat.com/riel/vmsplit/Also, do you have a public git repo that you regularly publish to for this patchset? If not a git repo do you put the raw patchset on some http/ftp server?
Up to now I have only emailed out the patches. Since there is demand for them to be downloadable from somewhere, I'll also start putting them on http://people.redhat.com/riel/
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Quoted 14 lines · Rik van Riel
Quoted 3 lines · On Wed, 9 Jan 2008 23:39:02 -0500 "Mike Snitzer" <[email protected]> wrote:
How much trouble am I asking for if I were to try to get your patchset to fly on a fairly recent "stable" kernel (e.g. 2.6.22.15)? If workable, is such an effort before it's time relative to your TODO?
Quite a bit :)
The -mm kernel has the memory controller code, which means the
mm/directory is fairly different. My patch set sits on top of that.
Quoted 5 lines
Chances are that once the -mm kernel goes upstream (in 2.6.25-rc1), I can start building on top of that.
OTOH, maybe I could get my patch series onto a recent 2.6.23.X with minimal chainsaw effort.
That would be great! I can't speak for others but -mm poses a problem for testing your patchset because it is so bleeding. Let me know if you take the plunge on a 2.6.23.x backport; I'd really appreciate it.
Is anyone else interested in consuming a 2.6.23.x backport of Rik's patchset? If so please speak up.
Quoted 10 lines
Quoted 6 lines
I see that you have an old port to a FC7-based 2.6.21 here:
http://people.redhat.com/riel/vmsplit/Also, do you have a public git repo that you regularly publish to for this patchset? If not a git repo do you put the raw patchset on some http/ftp server?
Up to now I have only emailed out the patches. Since there is demand for them to be downloadable from somewhere, I'll also start putting them on http://people.redhat.com/riel/
Great, thanks.
Mike
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Quoted 24 lines · Rik van Riel
On large memory systems, the VM can spend way too much time scanning through pages that it cannot (or should not) evict from memory. Not only does it use up CPU time, but it also provokes lock contention and can leave large systems under memory presure in a catatonic state.
Against 2.6.24-rc6-mm1
This patch series improves VM scalability by:
1) making the locking a little more scalable
2) putting filesystem backed, swap backed and non-reclaimable pages onto their own LRUs, so the system only scans the pages that it can/should evict from memory
3) switching to SEQ replacement for the anonymous LRUs, so the number of pages that need to be scanned when the system starts swapping is bound to a reasonable number
More info on the overall design can be found at:
Quoted 9 lines
Changelog:
- merge memcontroller split LRU code into the main split LRU patch, since it is not functionally different (it was split up only to help people who had seen the last version of the patch series review it)
- drop thepage_file_cachedebugging patch, since it never triggered
- reintroduce code to not scan anon list if swap is full
- add code to scan anon list if page cache is very small already
- use lumpy reclaim more aggressively for smaller order > 1 allocations
Hi, Rik,
I've just started the patch series, the compile fails for me on a powerpc box. global_lru_pages() is defined under CONFIG_PM, but used else where in mm/page-writeback.c. None of the global_lru_pages() parameters depend on CONFIG_PM. Here's a simple patch to fix it.
mm/page-writeback.c +0 -0
mm/vmscan.c +8 -8
@@ -1920,6 +1920,14 @@ void wakeup_kswapd(struct zone *zone, int order)wake_up_interruptible (&pgdat->kswapd_wait); } +unsigned long global_lru_pages (void ) +{ +return global_page_state (NR_ACTIVE_ANON ) + +global_page_state (NR_ACTIVE_FILE ) + +global_page_state (NR_INACTIVE_ANON ) + +global_page_state (NR_INACTIVE_FILE ); +} +#ifdef CONFIG_PM /* * Helper function for shrink_all_memory(). Tries to reclaim 'nr_pages' pages
@@ -1968,14 +1976,6 @@ static unsigned long shrink_all_zones(unsigned long nr_pages, int prio,return ret; } -unsigned long global_lru_pages (void ) -{ -return global_page_state (NR_ACTIVE_ANON ) - +global_page_state (NR_ACTIVE_FILE ) - +global_page_state (NR_INACTIVE_ANON ) - +global_page_state (NR_INACTIVE_FILE ); -} -/* * Try to free `nr_pages' of memory, system-wide, and return the number of * freed pages.
Signature · 10 lines
Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Quoted 4 lines · On Fri, 11 Jan 2008 16:11:15 +0530 Balbir Singh <[email protected]>…
I've just started the patch series, the compile fails for me on a powerpc box.
global_lru_pages()is defined underCONFIG_PM, but used else where inmm/page-writeback.c. None of theglobal_lru_pages()parameters depend onCONFIG_PM. Here's a simple patch to fix it.
Thank you for the fix. I have applied it to my tree.
Signature · 7 lines
All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
Quoted 4 lines · Rik van Riel
Changelog:
- merge memcontroller split LRU code into the main split LRU patch, since it is not functionally different (it was split up only to help people who had seen the last version of the patch series review it)
Hi, Rik,
I see a strange behaviour with this patchset. I have a program (pagetest from Vaidy), that does the following
1. Can allocate different kinds of memory, mapped, malloc'ed or shared
2. Allocates and touches all the memory in a loop (2 times)
I mount the memory controller and limit it to 400M and run pagetest and ask it to touch 1000M. Without this patchset everything runs fine, but with this patchset installed, I immediately see
pagetest invoked oom-killer: gfp_mask=0xd0, order=0, oomkilladj=0
Call Trace: [c0000000e5aef400] [c00000000000eb24] .show_stack+0x70/0x1bc (unreliable) [c0000000e5aef4b0] [c0000000000bbbbc] .oom_kill_process+0x80/0x260 [c0000000e5aef570] [c0000000000bc498] .mem_cgroup_out_of_memory+0x6c/0x98 [c0000000e5aef610] [c0000000000f2574] .mem_cgroup_charge_common+0x1e0/0x414 [c0000000e5aef6e0] [c0000000000b852c] .add_to_page_cache+0x48/0x164 [c0000000e5aef780] [c0000000000b8664] .add_to_page_cache_lru+0x1c/0x68 [c0000000e5aef810] [c00000000012db50] .mpage_readpages+0xbc/0x15c [c0000000e5aef940] [c00000000018bdac] .ext3_readpages+0x28/0x40 [c0000000e5aef9c0] [c0000000000c3978] .__do_page_cache_readahead+0x158/0x260 [c0000000e5aefa90] [c0000000000bac44] .filemap_fault+0x18c/0x3d4 [c0000000e5aefb70] [c0000000000cd510] .__do_fault+0xb0/0x588 [c0000000e5aefc80] [c0000000005653cc] .do_page_fault+0x440/0x620 [c0000000e5aefe30] [c000000000005408] handle_page_fault+0x20/0x58 Mem-info: Node 0 DMA per-cpu: CPU 0: hi: 6, btch: 1 usd: 4 CPU 1: hi: 6, btch: 1 usd: 0 CPU 2: hi: 6, btch: 1 usd: 3 CPU 3: hi: 6, btch: 1 usd: 4 Active_anon:9099 active_file:1523 inactive_anon0 inactive_file:2869 noreclaim:0 dirty:20 writeback
:0 unstable:0
free:44210 slab:639 mapped:1724 pagetables:475 bo
unce:0
Node 0 DMA free:2829440kB min:7808kB low:9728kB hi
gh:11712kB active_anon:582336kB inactive_anon:0kB active_file:97472kB inactive_f ile:183616kB noreclaim:0kB present:3813760kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0
Node 0 DMA: 3*64kB 5*128kB 5*256kB 4*512kB 2*1024k
B 4*2048kB 3*4096kB 2*8192kB 170*16384kB = 2828352kB
Swap cache: add 0, delete 0, find 0/0
Free swap = 3148608kB
Total swap = 3148608kB
Free swap: 3148608kB
59648 pages of RAM
677 reserved pages
28165 pages shared
0 pages swap cached
Memory cgroup out of memory: kill process 6593 (pagetest) score 1003 or a child Killed process 6593 (pagetest)
I am using a powerpc box with 64K size pages. I'll try and investigate further, just a heads up on the failure I am seeing.
Signature · 10 lines
Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
rvr split LRU minor regression ?
In reply to Rik van RielHi Rik
I tested new hackbench on rvr split LRU patch.
new hackbench URL is
http://people.redhat.com/mingo/cfs-scheduler/tools/hackbench.c
method of test
(1) $ ./hackbench 150 process 1000
(2) # sync; echo 3 > /proc/sys/vm/drop_caches
$ dd if=tmp10G of=/dev/null
$ ./hackbench 150 process 1000test machine:
CPU: x86_64 1.86GHz x2
memory: 6GB
result:
2.6.24-rc6-mm1 +rvr-split-lru ratio
(small is faster)
-------------------------------------------------------------------
(1) 364.981 359.386 98.47% (2) 364.461 387.471 106.31%
more detail:
1. /usr/bin/time command output
vanilla 2.6.24-rc6-mm1
33.74user 703.10system 6:09.56elapsed 199%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+372467minor)pagefaults 0swaps
2.6.24-rc6-mm1 + rvr-split-lru
36.22user 731.30system 6:35.16elapsed 194%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (804major+389524minor)pagefaults 0swaps
It seems increase page fault.
2.
after test (2), cat /proc/meminfo
vanilla 2.6.24-rc6-mm1
MemTotal: 5931808 kB
MemFree: 1751632 kB
Buffers: 4360 kB
Cached: 3930020 kB
SwapCached: 0 kB
Active: 46396 kB
Inactive: 3924108 kB
SwapTotal: 20972848 kB
SwapFree: 20972720 kB
Dirty: 0 kB
Writeback: 0 kB
AnonPages: 36140 kB
Mapped: 10104 kB
Slab: 160020 kB
SReclaimable: 3460 kB
SUnreclaim: 156560 kB
PageTables: 3712 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
CommitLimit: 23938752 kB
Committed_AS: 78940 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 57220 kB
VmallocChunk: 34359680999 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB
2.6.24-rc6-mm1 + rvr-split-lru
MemTotal: 5931356 kB MemFree: 1771800 kB Buffers: 2776 kB Cached: 3914800 kB SwapCached: 7940 kB Active(anon): 21868 kB Inactive(anon): 6560 kB Active(file): 1722888 kB Inactive(file): 2192128 kB Noreclaim: 3472 kB Mlocked: 3724 kB SwapTotal: 20972848 kB SwapFree: 20935032 kB Dirty: 8 kB Writeback: 0 kB AnonPages: 23912 kB Mapped: 9500 kB Slab: 162188 kB SReclaimable: 5544 kB SUnreclaim: 156644 kB PageTables: 4444 kB NFS_Unstable: 0 kB Bounce: 0 kB CommitLimit: 23938524 kB Committed_AS: 106816 kB VmallocTotal: 34359738367 kB VmallocUsed: 57220 kB VmallocChunk: 34359680999 kB HugePages_Total: 0 HugePages_Free: 0 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 2048 kB
It seems used once memory incorrect activation increased. What do you think it?
- kosaki
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>