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
The noreclaim patches come verbatim from Lee Schermerhorn and Nick Piggin. I have made a few small fixes to them and left out the bits that are no longer needed with split file/anon lists.
The exception is "Scan noreclaim list for reclaimable pages", which should not be needed but could be a useful debugging tool.
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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
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mm/vmscan.c +41 -0
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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)
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PATCH 2/19 free swap space on swap-in/activation
In reply to [email protected]+ 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,
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PATCH 3/19 define page_file_cache() function
In reply to [email protected]Define 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);
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PATCH 4/19 debugging checks for page_file_cache()
In reply to [email protected]Debug whether we end up classifying the wrong pages as filesystem backed. This has not triggered in stress tests on my system, but who knows...
DEBUGGING ONLY: NOT FOR UPSTREAM MERGE
include/linux/mm_inline.h +10 -0
@@ -1,6 +1,8 @@#ifndef LINUX_MM_INLINE_H #define LINUX_MM_INLINE_H +#include <linux/fs.h> /* for struct address_space */ +/** * page_file_cache(@page) * Returns !0 if @page is page cache page backed by a regular filesystem,
@@ -10,11 +12,19 @@* needs to survive until the page is last deleted from the LRU, which * could be as far down as __page_cache_release. */ +extern const struct address_space_operations shmem_aops;static inline int page_file_cache (struct page *page) { +struct address_space * mapping =page_mapping (page); +if (PageSwapBacked (page))return 0 ; +/* These pages should all be marked PG_swapbacked */ +WARN_ON (PageAnon (page)); +WARN_ON (PageSwapCache (page)); +WARN_ON (mapping && mapping->a_ops && mapping->a_ops == &shmem_aops); +/* The page is page cache backed by a normal filesystem. */ return 2 ; }
mm/shmem.c +2 -2
@@ -179,7 +179,7 @@ static inline void shmem_unacct_blocks(u }static const struct super_operations shmem_ops; -static const struct address_space_operations shmem_aops; +const struct address_space_operations shmem_aops;static const struct file_operations shmem_file_operations;static const struct inode_operations shmem_inode_operations;static const struct inode_operations shmem_dir_inode_operations;
@@ -2344,7 +2344,7 @@ static void destroy_inodecache(void)kmem_cache_destroy (shmem_inode_cachep); } -static const struct address_space_operations shmem_aops = { +const struct address_space_operations shmem_aops = { .writepage = shmem_writepage, .set_page_dirty = __set_page_dirty_no_writeback, #ifdef CONFIG_TMPFS
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PATCH 5/19 Use an indexed array for LRU variables
In reply to [email protected]V1 -> 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);
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PATCH 6/19 split LRU lists into anon & file sets
In reply to [email protected]Split 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. Fancy policy changes will be 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 +200 -222
735 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 +1 -1
@@ -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);
mm/memcontrol.c +7 -2
@@ -30,6 +30,7 @@#include <linux/spinlock.h> #include <linux/fs.h> #include <linux/seq_file.h> +#include <linux/mm_inline.h> #include <asm/uaccess.h>
@@ -509,7 +510,7 @@ unsigned long mem_cgroup_isolate_pages(u unsigned long *scanned, int order, int mode, struct zone *z, struct mem_cgroup *mem_cont, - int active) + int active, int file) { unsigned long nr_taken = 0;struct page *page;
@@ -521,6 +522,7 @@ unsigned long mem_cgroup_isolate_pages(uint zid =zone_idx (z);struct mem_cgroup_per_zone *mz; +/* TODO: split file and anon LRUs - Rik */ mz =mem_cgroup_zoneinfo (mem_cont, nid, zid);if (active) src = &mz->active_list;
@@ -539,6 +541,9 @@ unsigned long mem_cgroup_isolate_pages(uif (unlikely (!PageLRU (page)))continue ; +/* +* TODO: play better with lumpy reclaim, grabbing anything. +*/ if (PageActive (page) && !active) {__mem_cgroup_move_lists (pc, true);continue ;
@@ -551,7 +556,7 @@ unsigned long mem_cgroup_isolate_pages(u scan++;list_move (&pc->lru, &pc_list); -if (__isolate_lru_page (page, mode) ==0 ) { +if (__isolate_lru_page (page, mode, file) ==0 ) {list_move (&page->lru, dst); nr_taken++; }
Signature · 1 line
All Rights Reversed
Re: [patch 06/19] split LRU lists into anon & file sets
Quoted 13 lines · On Wed, 02 Jan 2008 17:41:50 -0500 [email protected] wrote:
static void shrink_active_list(unsigned long
nr_pages, struct zone *zone,mm/vmscan.c +2
-3- struct scan_control *sc, int priority) + struct scan_control *sc, int priority, int file) { unsigned long pgmoved;int pgdeactivate =0 ;@@ -1128,64 +1026,65 @@ static void shrink_active_list(unsignedstruct list_head list[NR_LRU_LISTS ];struct page *page;struct pagevec pvec; -int reclaim_mapped =0 ; -enum lru_list l; +enum lru_list lru;
<snip>
mm/vmscan.c static void shrink_active_list(unsigned · line 1055
Quoted 5 lines
mm/vmscan.c +5
-0+/* +* 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. +*/
This is not easy to read.... (this definition affects later patches...)
How about adding some new enum (only) for this function ? like
LRU_STAY_ACTIVE = 0,
LRU_MOVE_INACTIVE = 1,
Thanks,
-Kame
PATCH 7/19 split anon & file LRUs for memcontrol code
In reply to [email protected]Update the split anon & file LRU code to deal with the recent memory controller changes.
include/linux/memcontrol.h +5 -12
@@ -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 +67 -90
278 lines not on this page · raw message
mm/vmscan.c +14 -14
@@ -1230,13 +1230,13 @@ static unsigned long shrink_zone(int priget_scan_ratio (zone, sc, percent); -if (scan_global_lru (sc)) { -/* -* Add one to nr_to_scan just to make sure that the kernel -* will slowly sift through the active list. -*/ -for_each_lru (l) { +for_each_lru (l) { +if (scan_global_lru (sc)) {int file =is_file_lru (l); +/* +* Add one to nr_to_scan just to make sure that the +* kernel will slowly sift through the active list. +*/ zone->nr_scan[l] += (zone_page_state (zone,NR_INACTIVE_ANON + l) >> priority) +1 ; nr[l] = zone->nr_scan[l] * percent[file] /100 ;
@@ -1244,18 +1244,15 @@ static unsigned long shrink_zone(int pri zone->nr_scan[l] =0 ; else nr[l] =0 ; + }else { +/* +* This reclaim occurs not because zone memory shortage +* but because memory controller hits its limit. +* Then, don't modify zone reclaim related data. +*/ + nr[l] =mem_cgroup_calc_reclaim (sc->mem_cgroup, zone, + priority, l); } - }else { -/* -* This reclaim occurs not because zone memory shortage but -* because memory controller hits its limit. -* Then, don't modify zone reclaim related data. -*/ - nr[LRU_ACTIVE ] =mem_cgroup_calc_reclaim_active (sc->mem_cgroup, - zone, priority);
Re: [patch 07/19] split anon & file LRUs for memcontrol code
mm/vmscan.c static unsigned long shrink_zone(int pri · line 1232
Quoted 8 lines · On Wed, 02 Jan 2008 17:41:51 -0500 [email protected] wrote:
Index:
linux-2.6.24-rc6-mm1/mm/vmscan.c
===================================================================mm/vmscan.c +0
-0@@ -1230,13 +1230,13 @@ static unsigned long shrink_zone(int priget_scan_ratio (zone, sc, percent);
I'm happy if this calclation can be following later. ==
if (scan_global_lru(sc)) {
get_scan_ratio(zone, sc, percent);
} else {
get_scan_ratio_cgroup(sc->cgroup, sc, percent);
}==
To do this,mem_cgroup needs to have recent_rotated_file and recent_rolated_anon ?
Thanks,
-Kame
Re: [patch 07/19] split anon & file LRUs for memcontrol code
Quoted 14 lines · KAMEZAWA Hiroyuki
mm/vmscan.c static unsigned long shrink_zone(int pri · line 1232
Quoted 8 lines · On Wed, 02 Jan 2008 17:41:51 -0500 [email protected] wrote:
Index:
linux-2.6.24-rc6-mm1/mm/vmscan.c
===================================================================mm/vmscan.c +0
-0@@ -1230,13 +1230,13 @@ static unsigned long shrink_zone(int priget_scan_ratio (zone, sc, percent);I'm happy if this calclation can be following later. ==
Quoted 8 lines
if (scan_global_lru(sc)) { get_scan_ratio(zone, sc, percent); } else { get_scan_ratio_cgroup(sc->cgroup, sc, percent); }==
To do this,mem_cgroupneeds to haverecent_rotated_fileandrecent_rolated_anon?
Yes, that makes sense.
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 07/19] split anon & file LRUs for memcontrol code
In reply to KAMEZAWA HiroyukiQuoted 14 lines · On Mon, 7 Jan 2008 19:04:55 +0900 KAMEZAWA Hiroyuki…
mm/vmscan.c static unsigned long shrink_zone(int pri · line 1232
Quoted 8 lines · On Wed, 02 Jan 2008 17:41:51 -0500 [email protected] wrote:
Index:
linux-2.6.24-rc6-mm1/mm/vmscan.c
===================================================================mm/vmscan.c +0
-0@@ -1230,13 +1230,13 @@ static unsigned long shrink_zone(int priget_scan_ratio (zone, sc, percent);I'm happy if this calclation can be following later. ==
Quoted 8 lines
if (scan_global_lru(sc)) { get_scan_ratio(zone, sc, percent); } else { get_scan_ratio_cgroup(sc->cgroup, sc, percent); }==
To do this,mem_cgroupneeds to haverecent_rotated_fileandrecent_rolated_anon?
One possible problem could be that the cgroup can also have pages reclaimed in global reclaim, not just in local cgroup reclaims.
That is, these cgroup's pages can also disappear or get rotated without the cgroup's recent_rotated_file and recent_rotated_anon being affected at all.
Still, having the cgroup do the same thing as the global zones is probably the best approximation.
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 SEQ replacement for anonymous pages
In reply to [email protected]We 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 · 1 line
All Rights Reversed
PATCH 9/19 add newly swapped in pages to the inactive list
In reply to [email protected]Swapin_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 · 1 line
All Rights Reversed
PATCH 10/19 No Reclaim LRU Infrastructure
In reply to [email protected]V1 -> 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
@@ -92,13 +92,36 @@ 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 · 1 line
All Rights Reversed
PATCH 11/19 Non-reclaimable page statistics
In reply to [email protected]V2 -> 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 · 1 line
All Rights Reversed
PATCH 12/19 scan noreclaim list for reclaimable pages
In reply to [email protected]V2 -> 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 · 1 line
All Rights Reversed
PATCH 13/19 ramfs pages are non-reclaimable
In reply to [email protected]V3 -> 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
@@ -2237,6 +2237,7 @@ 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
@@ -2246,6 +2247,9 @@ 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 · 1 line
All Rights Reversed
PATCH 14/19 SHM_LOCKED pages are nonreclaimable
In reply to [email protected]V2 -> 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
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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 · 1 line
All Rights Reversed
PATCH 15/19 non-reclaimable mlocked pages
In reply to [email protected]V2 -> 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 · 1 line
All Rights Reversed
PATCH 16/19 mlock vma pages under mmap_sem held for read
In reply to [email protected]V2 -> 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 · 1 line
All Rights Reversed
PATCH 17/19 handle mlocked pages during map/unmap and truncate
In reply to [email protected]V2 -> 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 · 1 line
All Rights Reversed
PATCH 18/19 account mlocked pages
In reply to [email protected]V2 -> 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 · 1 line
All Rights Reversed
PATCH 19/19 cull non-reclaimable anon pages from the LRU at fault time
In reply to [email protected]V2 -> 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 · 1 line
All Rights Reversed
cover VM pageout scalability - one big patch
In reply to [email protected]By popular request, here are all the VM pageout scalability patches rolled up into one big patch.
drivers/base/node.c | 65 +- drivers/block/brd.c | 13 fs/cifs/file.c | 4 fs/nfs/dir.c | 2 fs/ntfs/file.c | 4 fs/proc/proc_misc.c | 78 +- fs/ramfs/file-nommu.c | 4 fs/ramfs/inode.c | 1 include/linux/memcontrol.h | 19 include/linux/migrate.h | 3 include/linux/mm_inline.h | 136 ++++- include/linux/mmzone.h | 66 ++ include/linux/page-flags.h | 43 + include/linux/pagemap.h | 28 + include/linux/pagevec.h | 22 include/linux/rmap.h | 12 include/linux/swap.h | 44 + include/linux/vmstat.h | 10 kernel/sysctl.c | 10 mm/Kconfig | 24 mm/filemap.c | 19 mm/internal.h | 57 ++ mm/memcontrol.c | 170 ++---- mm/memory.c | 13 mm/mempolicy.c | 12 mm/migrate.c | 87 +-- mm/mlock.c | 290 ++++++++++ mm/mmap.c | 42 + mm/mremap.c | 8 mm/page-writeback.c | 8 mm/page_alloc.c | 110 +++- mm/readahead.c | 2 mm/rmap.c | 160 +++++ mm/shmem.c | 8 mm/swap.c | 249 ++++++++- mm/swap_state.c | 6 mm/truncate.c | 4 mm/vmscan.c | 939 ++++++++++++++++++++++++----------- mm/vmstat.c | 25 39 files changed, 2171 insertions(+), 626 deletions(-)
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 +57 -0
66 lines not on this page · raw message
mm/migrate.c +45 -42
136 lines not on this page · raw message
mm/vmscan.c +665 -274
1,282 lines not on this page · raw message
mm/mempolicy.c +9 -3
@@ -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)
@@ -1906,7 +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/swap.c +220 -29
368 lines not on this page · raw message
include/linux/pagevec.h +18 -4
@@ -23,9 +23,17 @@ 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); +#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,pgoff_t start,unsigned nr_pages); unsigned pagevec_lookup_tag(struct pagevec *pvec,
@@ -81,10 +89,16 @@ 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/mm_inline.h +120 -16
160 lines not on this page · raw message
mm/shmem.c +6 -2
@@ -179,7 +179,7 @@ static inline void shmem_unacct_blocks(u }static const struct super_operations shmem_ops; -static const struct address_space_operations shmem_aops; +const struct address_space_operations shmem_aops;static const struct file_operations shmem_file_operations;static const struct inode_operations shmem_inode_operations;static const struct inode_operations shmem_dir_inode_operations;
@@ -1377,6 +1377,7 @@ repeat: goto failed; } +SetPageSwapBacked (filepage);spin_lock (&info->lock); entry =shmem_swp_alloc (info, idx, sgp);if (IS_ERR (entry))
@@ -1467,10 +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:
@@ -2343,7 +2347,7 @@ static void destroy_inodecache(void)kmem_cache_destroy (shmem_inode_cachep); } -static const struct address_space_operations shmem_aops = { +const struct address_space_operations shmem_aops = { .writepage = shmem_writepage, .set_page_dirty = __set_page_dirty_no_writeback, #ifdef CONFIG_TMPFS
include/linux/page-flags.h +43 -0
77 lines not on this page · raw message
mm/memory.c +8 -5
@@ -1664,7 +1664,8 @@ gotten:ptep_clear_flush (vma, address, page_table);set_pte_at (mm, address, page_table, entry);update_mmu_cache (vma, address, entry); -lru_cache_add_active (new_page); +SetPageSwapBacked (new_page); +lru_cache_add_active_or_noreclaim (new_page, vma);page_add_new_anon_rmap (new_page, vma, address);/* Free the old page.. */
@@ -2131,7 +2132,8 @@ static int do_anonymous_page(struct mm_sif (!pte_none (*page_table)) goto release;inc_mm_counter (mm, anon_rss); -lru_cache_add_active (page); +SetPageSwapBacked (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);
@@ -2283,9 +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); -lru_cache_add_active (page); -page_add_new_anon_rmap (page, vma, address); +inc_mm_counter (mm, anon_rss); +SetPageSwapBacked (page); +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 +5 -1
@@ -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 );
@@ -299,7 +300,10 @@ struct page *read_swap_cache_async(swp_e/* * Initiate read into locked page and return. */ -lru_cache_add_active (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; }
mm/page_alloc.c +98 -12
191 lines not on this page · raw message
include/linux/mmzone.h +59 -7
102 lines not on this page · raw message
mm/vmstat.c +19 -6
@@ -686,8 +686,16 @@ 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" , +#ifdef CONFIG_NORECLAIM +"nr_noreclaim" , +#endif +#ifdef CONFIG_NORECLAIM_MLOCK +"nr_mlock" , +#endif"nr_anon_pages" ,"nr_mapped" ,"nr_file_pages" ,
@@ -750,7 +758,7 @@ 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),
@@ -758,7 +766,10 @@ 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_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);
@@ -795,10 +806,12 @@ 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' ); }
fs/proc/proc_misc.c +47 -31
90 lines not on this page · raw message
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 +43 -22
94 lines not on this page · raw message
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 +16 -3
@@ -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; }
@@ -2520,8 +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);
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 +41 -3
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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,
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mm/memcontrol.c +78 -92
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mm/mlock.c +279 -11
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mm/rmap.c +135 -25
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mm/mmap.c +37 -5
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Quoted 5 lines · On Wed, 02 Jan 2008 17:41:44 -0500 [email protected] wrote:
This patch series improves VM scalability by:
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
I have done some (minimal) testing of this tonight.
Running a 16000 MB fillmem on my 16GB test box (where slub eats up unexplainable amounts of memory so the test gets about 14GB RSS and 1.5GB in swap).
2.6.24-rc6-mm1
$ time ./fillmem 16000 real 3m43.601s user 0m11.090s sys 0m55.274s
2.6.24-rc6-mm1-vmsplit
$ time ./fillmem 16000 real 1m51.323s user 0m10.638s sys 0m42.859s
This is after carefully emptying out all memory by rebooting the system and running fillmem a few times. These results are repeatable.
With vanilla 2.6.24-rc6-mm1, kswapd eats up 99% of the CPU at a few points in the test run. This never seems to happen with the vmsplit kernel.
Unfortunately the symbol file for vanilla 2.6.24-rc6-mm1 seems to be hosed, so readprofile is not returning anything useful on that kernel. I'll try to come up with more useful data later.
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Quoted 3 lines · Rik van Riel
Running a 16000 MB fillmem on my 16GB test box (where slub eats up unexplainable amounts of memory so the test gets about 14GB RSS and 1.5GB in swap).
SLUB eats up process memory? Slab allocations are not charged to the process. But there is new code in mm so there could be a problem somewhere. Could you give me more details?
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Quoted 9 lines · On Wed, 9 Jan 2008 18:39:15 -0800 (PST) Christoph Lameter <[email protected]>…
Quoted 3 lines · Rik van Riel
Running a 16000 MB fillmem on my 16GB test box (where slub eats up unexplainable amounts of memory so the test gets about 14GB RSS and 1.5GB in swap).
SLUB eats up process memory? Slab allocations are not charged to the process. But there is new code in mm so there could be a problem somewhere. Could you give me more details?
IIRC /proc/meminfo reported that there were a few hundred MB in slab, despite the system only running the few daemons that get started by default and my one fillmem process.
I'll get you more details once /proc/slabinfo works again.
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Quoted 19 lines · On Wed, 2008-01-02 at 17:41 -0500, [email protected] wrote:
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
Quoted 6 lines
The noreclaim patches come verbatim from Lee Schermerhorn and Nick Piggin. I have made a few small fixes to them and left out the bits that are no longer needed with split file/anon lists.
The exception is "Scan noreclaim list for reclaimable pages", which should not be needed but could be a useful debugging tool.
Note that patch 14/19 [SHM_LOCK/UNLOCK handling] depends on the infrastructure introduced by the "Scan noreclaim list for reclaimable pages" patch. When SHM_UNLOCKing a shm segment, we call a new scan_mapping_noreclaim_page() function to check all of the pages in the segment for reclaimability. There might be other reasons for the pages to be non-reclaimable...
So, we can't merge 14/19 as is w/o some of patch 12. We can probably eliminate the sysctl and per node sysfs attributes to force a scan. But, as Rik says, this has been useful for debugging--e.g., periodically forcing a full rescan while running a stress load.
Also, I should point out that the full noreclaim series includes a couple of other patches NOT posted here by Rik:
1) treat swap backed pages as nonreclaimable when no swap space is available. This addresses a problem we've seen in real life, with vmscan spending a lot of time trying to reclaim anon/shmem/tmpfs/... pages only to find that there is no swap space--add_to_swap() fails. Maybe not a problem with Rik's new anon page handling. We'll see. If we did want to add this filter, we'll need a way to bring back pages from the noreclaim list that are there only for lack of swap space when space is added or becomes available.
2) treat anon pages with "excessively long" anon_vma lists as
nonreclaimable. "excessively long" here is a sysctl tunable parameter.
This also addresses problems we've seen with benchmarks and stress tests--all cpus spinning on some anon_vma lock. In "real life", we've seen this behavior with file backed pages--spinning on the i_mmap_lock--running Oracle workloads with user counts in the few thousands. Again, something we may not need with Rik's vmscan rework. If we did want to do this, we'd probably want to address file backed pages and add support to bring the pages back from the noreclaim list when the number of "mappers" drops below the threshold. My current patch leaves anon pages as non-reclaimable until they're freed, or manually scanned via the mechanism introduced by patch 12.
Lee
Quoted 1 line
Quoted 8 lines · On Thu, 03 Jan 2008 11:52:08 -0500 Lee Schermerhorn <[email protected]>…
Also, I should point out that the full noreclaim series includes a couple of other patches NOT posted here by Rik:
1) treat swap backed pages as nonreclaimable when no swap space is available. This addresses a problem we've seen in real life, with vmscan spending a lot of time trying to reclaim anon/shmem/tmpfs/... pages only to find that there is no swap space--add_to_swap() fails. Maybe not a problem with Rik's new anon page handling.
If there is no swap space, my VM code will not bother scanning any anon pages. This has the same effect as moving the pages to the no-reclaim list, with the extra benefit of being able to resume scanning the anon lists once swap space is freed.
Quoted 4 lines
2) treat anon pages with "excessively long"
anon_vmalists as
nonreclaimable. "excessively long" here is a sysctl tunable parameter.
This also addresses problems we've seen with benchmarks and stress tests--all cpus spinning on someanon_vmalock. In "real life", we've
Quoted 8 lines
seen this behavior with file backed pages--spinning on the i_mmap_lock--running Oracle workloads with user counts in the few thousands. Again, something we may not need with Rik's vmscan rework. If we did want to do this, we'd probably want to address file backed pages and add support to bring the pages back from the noreclaim list when the number of "mappers" drops below the threshold. My current patch leaves anon pages as non-reclaimable until they're freed, or manually scanned via the mechanism introduced by patch 12.
I can see some issues with that patch. Specifically, if the threshold is set too high no pages will be affected, and if the threshold is too low all pages will become non-reclaimable, leading to a false OOM kill.
Not only is it a very big hammer, it's also a rather awkward one...
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Quoted 30 lines · Rik van Riel
Quoted 8 lines · On Thu, 03 Jan 2008 11:52:08 -0500 Lee Schermerhorn <[email protected]>…
Also, I should point out that the full noreclaim series includes a couple of other patches NOT posted here by Rik:
1) treat swap backed pages as nonreclaimable when no swap space is available. This addresses a problem we've seen in real life, with vmscan spending a lot of time trying to reclaim anon/shmem/tmpfs/... pages only to find that there is no swap space--add_to_swap() fails. Maybe not a problem with Rik's new anon page handling.
If there is no swap space, my VM code will not bother scanning any anon pages. This has the same effect as moving the pages to the no-reclaim list, with the extra benefit of being able to resume scanning the anon lists once swap space is freed.
Quoted 4 lines
2) treat anon pages with "excessively long"
anon_vmalists as
nonreclaimable. "excessively long" here is a sysctl tunable parameter.
This also addresses problems we've seen with benchmarks and stress tests--all cpus spinning on someanon_vmalock. In "real life", we'veQuoted 8 lines
seen this behavior with file backed pages--spinning on the i_mmap_lock--running Oracle workloads with user counts in the few thousands. Again, something we may not need with Rik's vmscan rework. If we did want to do this, we'd probably want to address file backed pages and add support to bring the pages back from the noreclaim list when the number of "mappers" drops below the threshold. My current patch leaves anon pages as non-reclaimable until they're freed, or manually scanned via the mechanism introduced by patch 12.
Quoted 5 lines
I can see some issues with that patch. Specifically, if the threshold is set too high no pages will be affected, and if the threshold is too low all pages will become non-reclaimable, leading to a false OOM kill.
Not only is it a very big hammer, it's also a rather awkward one...
Yes, but the problem, when it occurs, is very awkward. The system just hangs for hours/days spinning on the reverse mapping locks--in both page_referenced() and try_to_unmap(). No pages get reclaimed and NO OOM kill occurs because we never get that far. So, I'm not sure I'd call any OOM kills resulting from this patch as "false". The memory is
effectively nonreclaimable. Now, I think that your anon pages SEQ
patch will eliminate the contention in page_referenced[_anon](), but we could still hang in try_to_unmap(). And we have the issue with file back pages and the i_mmap_lock. I'll see if this issue comes up in testings with the current series. If not, cool! If so, we just have more work to do.
Later,
Lee
Quoted 1 line
Quoted 8 lines · On Thu, 03 Jan 2008 12:13:32 -0500 Lee Schermerhorn <[email protected]>…
Yes, but the problem, when it occurs, is very awkward. The system just hangs for hours/days spinning on the reverse mapping locks--in both
page_referenced()andtry_to_unmap(). No pages get reclaimed and NO OOM kill occurs because we never get that far. So, I'm not sure I'd call any OOM kills resulting from this patch as "false". The memory is
effectively nonreclaimable. Now, I think that your anon pages SEQ
patch will eliminate the contention in page_referenced[_anon](), but we could still hang intry_to_unmap().
I am hoping that Nick's ticket spinlocks will fix this problem.
Would you happen to have any test cases for the above problem that I could use to reproduce the problem and look for an automatic fix?
Any fix that requires the sysadmin to tune things _just_ right seems too dangerous to me - especially if a change in the workload can result in the system doing exactly the wrong thing...
The idea is valid, but it just has to work automagically.
Btw, if page_referenced() is called less, the locks that try_to_unmap() also takes should get less contention.
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Quoted 12 lines · Rik van Riel
Quoted 8 lines · On Thu, 03 Jan 2008 12:13:32 -0500 Lee Schermerhorn <[email protected]>…
Yes, but the problem, when it occurs, is very awkward. The system just hangs for hours/days spinning on the reverse mapping locks--in both
page_referenced()andtry_to_unmap(). No pages get reclaimed and NO OOM kill occurs because we never get that far. So, I'm not sure I'd call any OOM kills resulting from this patch as "false". The memory is
effectively nonreclaimable. Now, I think that your anon pages SEQ
patch will eliminate the contention in page_referenced[_anon](), but we could still hang intry_to_unmap().
Quoted 4 lines
I am hoping that Nick's ticket spinlocks will fix this problem.
Would you happen to have any test cases for the above problem that I could use to reproduce the problem and look for an automatic fix?
We can easily [he says, glibly] reproduce the hang on the anon_vma lock with AIM7 loads on our test platforms. Perhaps we can come up with an AIM workload to reproduce the phenomenon on one of your test platforms. I've seen the hang with 15K-20K tasks on a 4 socket x86_64 with 16-32G of memory and quite a bit of storage.
I've also seen related hangs on both anon_vma and i_mmap_lock during a heavy usex stress load on the splitlru+noreclaim patches. [This, by the way, without and WITH my rw_lock patches for both anon_vma and i_mmap_lock.] I can try to package up the workload to run on your system.
Quoted 9 lines
Any fix that requires the sysadmin to tune things _just_ right seems too dangerous to me - especially if a change in the workload can result in the system doing exactly the wrong thing...
The idea is valid, but it just has to work automagically.
Btw, if
page_referenced()is called less, the locks thattry_to_unmap()also takes should get less contention.
Makes sense. we'll have to see.
Lee
Quoted 1 line
Quoted 1 line · Lee Schermerhorn
We can easily [he says, glibly] reproduce the hang on the
anon_vmalock
Is that a NUMA platform? On non x86? Perhaps you just need queued spinlocks?
-Andi
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Quoted 5 lines · On Fri, 04 Jan 2008 17:34:00 +0100 Andi Kleen <[email protected]> wrote:
Quoted 1 line · Lee Schermerhorn
We can easily [he says, glibly] reproduce the hang on the
anon_vmalockIs that a NUMA platform? On non x86? Perhaps you just need queued spinlocks?
I really think that the anon_vma and i_mmap_lock spinlock hangs are due to the lack of queued spinlocks. Not because I have seen your system hang, but because I've seen one of Larry's test systems here hang in scary/amusing ways :)
With queued spinlocks the system should just slow down, not hang.
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Quoted 11 lines · Rik van Riel
Quoted 7 lines · On Fri, 04 Jan 2008 17:34:00 +0100 Andi Kleen <[email protected]> wrote:
Quoted 3 lines · Lee Schermerhorn
We can easily [he says, glibly] reproduce the hang on the
anon_vmalock
Quoted 9 lines
Quoted 3 lines
Is that a NUMA platform? On non x86? Perhaps you just need queued spinlocks?
I really think that the
anon_vmaandi_mmap_lockspinlock hangs are due to the lack of queued spinlocks. Not because I have seen your system hang, but because I've seen one of Larry's test systems here hang in scary/amusing ways :)
Changing the anon_vma->lock into a rwlock_t helps because page_lock_anon_vma() can take it for read and thats where the contention is. However its the fact that under some tests, most of the pages are in vmas queued to one anon_vma that causes so much lock contention.
Quoted 5 lines
With queued spinlocks the system should just slow down, not hang.
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Quoted 5 lines · Andi Kleen
Quoted 1 line · Lee Schermerhorn
We can easily [he says, glibly] reproduce the hang on the
anon_vmalockIs that a NUMA platform? On non x86? Perhaps you just need queued spinlocks?
We see this on both NUMA and non-NUMA. x86_64 and ia64. The basic criteria to reproduce is to be able to run thousands [or low 10s of thousands] of tasks, continually increasing the number until the system just goes into reclaim. Instead of swapping, the system seems to hang--unresponsive from the console, but with "soft lockup" messages spitting out every few seconds...
Lee
Quoted 2 lines
-Andi
Quoted 6 lines · Lee Schermerhorn
We see this on both NUMA and non-NUMA.
x86_64and ia64. The basic criteria to reproduce is to be able to run thousands [or low 10s of thousands] of tasks, continually increasing the number until the system just goes into reclaim. Instead of swapping, the system seems to hang--unresponsive from the console, but with "soft lockup" messages spitting out every few seconds...
Ditto here.
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Quoted 10 lines · On Mon, 7 Jan 2008 11:07:54 -0800 (PST) Christoph Lameter <[email protected]>…
Quoted 6 lines · Lee Schermerhorn
We see this on both NUMA and non-NUMA.
x86_64and ia64. The basic criteria to reproduce is to be able to run thousands [or low 10s of thousands] of tasks, continually increasing the number until the system just goes into reclaim. Instead of swapping, the system seems to hang--unresponsive from the console, but with "soft lockup" messages spitting out every few seconds...Ditto here.
I have some suspicions on what could be causing this.
The most obvious suspect is get_scan_ratio() continuing to return 100 file reclaim, 0 anon reclaim when the file LRUs have already been reduced to something very small, because reclaiming up to that point was easy.
I plan to add some code to automatically set the anon reclaim to 100% if (free + file_active + file_inactive <= zone->pages_high), meaning that reclaiming just file pages will not be able to free enough pages.
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Quoted 12 lines · On Thu, 3 Jan 2008 12:00:00 -0500 Rik van Riel <[email protected]> wrote:
Quoted 8 lines · On Thu, 03 Jan 2008 11:52:08 -0500 Lee Schermerhorn <[email protected]>…
Also, I should point out that the full noreclaim series includes a couple of other patches NOT posted here by Rik:
1) treat swap backed pages as nonreclaimable when no swap space is available. This addresses a problem we've seen in real life, with vmscan spending a lot of time trying to reclaim anon/shmem/tmpfs/... pages only to find that there is no swap space--add_to_swap() fails. Maybe not a problem with Rik's new anon page handling.
Quoted 5 lines
If there is no swap space, my VM code will not bother scanning any anon pages. This has the same effect as moving the pages to the no-reclaim list, with the extra benefit of being able to resume scanning the anon lists once swap space is freed.
Is this 'avoiding scanning anon if no swap' feature in this set ?
Thanks
-Kame
Quoted 9 lines · On Mon, 7 Jan 2008 19:06:10 +0900 KAMEZAWA Hiroyuki…
Quoted 5 lines · On Thu, 3 Jan 2008 12:00:00 -0500 Rik van Riel <[email protected]> wrote:
If there is no swap space, my VM code will not bother scanning any anon pages. This has the same effect as moving the pages to the no-reclaim list, with the extra benefit of being able to resume scanning the anon lists once swap space is freed.
Is this 'avoiding scanning anon if no swap' feature in this set ?
I seem to have lost that code in a forward merge :(
Dunno if I started the forward merge from an older series that Lee had or if I lost the code myself...
I'll put it back in ASAP.
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