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2.6.21-mm1: many processes end up in D state

DISCUSSION Jiri Slaby 2 participants 8 messages Apr 30, 2007 – May 4, 2007

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Jiri Slaby

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#0 lore raw

Hi,

I have a problem with higher disk loads (e.g. running git-log or yum update). Many processes end up in D state and system is unusable -- I'm not able to run anything but smooth mouse moving when this happens.

If I wait for a 20-30sec it becomes usable. This happens in 2.6.21-rc7-mm2 and also in 2007-04-28-05-06 broken-out snapshot. I think 2.6.21-rc6-mm1 worked fine, but I'm uncertain. If it is important, let me know to re-test.

sysrq-t:

yum D 0000004C 0 2976 2955 (NOTLB)

       c455bd00 00200082 8c68ea9e 0000004c 00000000 00000000 c455bcdc c455bc9c
       c455bc9c c2d6a580 8c68ea9e 0000004c c455bcc0 c2d6a694 c1809980 00000000
       c455bcd0 c4640c80 000036a0 00000001 c455bcf0 c02a7132 c3682164 00001cde
Call Trace:
 [<c037834c>] io_schedule+0x21/0x2e
 [<c014d505>] sync_page+0x38/0x43
 [<c0378581>] __wait_on_bit_lock+0x40/0x63
 [<c014d4b6>] __lock_page+0x54/0x5c
 [<c014da81>] do_generic_mapping_read+0x1dc/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016d02c>] sys_pread64+0x64/0x68
 [<c0103ffc>] syscall_call+0x7/0xb
 [<47176012>] 0x47176012
 =======================
xterm         S 00000051     0  2980      1 (NOTLB)
       c4678ae0 00000082 b2fbf0ce 00000051 00000000 00000000 00000000 00000000
       c4678b30 c469d540 b2fbf0ce 00000051 c4678ab0 c469d654 c1813980 00000001
       c4678ad0 c47f0e40 c4678b00 00000286 c4678ae0 c012c077 00000001 00003286
Call Trace:
 [<c03784ad>] schedule_timeout+0x44/0xa4
 [<c0177ee3>] do_select+0x46d/0x55b
 [<c017816f>] core_sys_select+0x19e/0x2c0
 [<c01786f3>] sys_select+0xd3/0x18d
 [<c0103ffc>] syscall_call+0x7/0xb
 [<47180f98>] 0x47180f98
 =======================
bash          S 0000004A     0  2982   2980 (NOTLB)
       c50b3e80 00000086 ccf4cc7e 0000004a 00000000 c021bed9 00000000 c45c0030
       c50b3e30 c45c0030 ccf4cc7e 0000004a c50b3e50 c45c0144 c1809980 00000000
       c1809e44 c4517900 00000000 000000b3 c50b3e90 c014f841 c477cb40 c2d79000
Call Trace:
 [<c03784d3>] schedule_timeout+0x6a/0xa4
 [<c0221960>] read_chan+0x1b9/0x5b9
 [<c021e48f>] tty_read+0x75/0xaa
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016cf3d>] sys_read+0x3d/0x64
 [<c0103ffc>] syscall_call+0x7/0xb
 [<4717883e>] 0x4717883e
 =======================
metacity      S 00000050     0  3005   2429 (NOTLB)
       c2fd5bb0 00000086 5205656d 00000050 00000000 00000000 00000000 c441c51c
       00000246 c45c0540 5205656d 00000050 c2fd5b80 c45c0654 c1809980 00000000
       c1813e44 c27f4900 00002cb8 00000246 c2fd5ba0 c0135a80 c2fd5ba8 00002cb2
Call Trace:
 [<c03784d3>] schedule_timeout+0x6a/0xa4
 [<c0177905>] do_sys_poll+0x33f/0x46d
 [<c0177a74>] sys_poll+0x41/0x43
 [<c0103ffc>] syscall_call+0x7/0xb
 [<4717e3a6>] 0x4717e3a6
 =======================
ccpd          D 0000004C     0  3009   2010 (NOTLB)
       c50abbb0 00000082 f08ef585 0000004c 00000000 00000000 c180abc0 c22fc788
       c50abba0 c505d070 f08ef585 0000004c 00000000 c505d184 c1809980 00000000
       c21167f0 c2fc6740 c5794e3c c31eff74 c5794310 c22fc788 00000002 00001e64
Call Trace:
 [<c01b64d9>] do_get_write_access+0x310/0x4f5
 [<c01b66d9>] journal_get_write_access+0x1b/0x2a
 [<c01b59ce>] __ext3_journal_get_write_access+0x19/0x3f
 [<c01aa5f6>] ext3_reserve_inode_write+0x53/0x6c
 [<c01aa62f>] ext3_mark_inode_dirty+0x20/0x37
 [<c01ad350>] ext3_dirty_inode+0x6b/0x6d
 [<c01868fb>] __mark_inode_dirty+0x2a/0x16d
 [<c017eacc>] touch_atime+0x84/0xd8
 [<c014dd08>] do_generic_mapping_read+0x463/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016fc6e>] kernel_read+0x36/0x48
 [<c016fd32>] prepare_binprm+0xb2/0xdf
 [<c0171322>] do_execve+0xe6/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================
bash          D 0000004D     0  3011   2859 (NOTLB)
       c471dc90 00000082 08f8373c 0000004d 00000000 00000000 c471dc30 c471dc2c
       c471dc2c c4670540 08f8373c 0000004d c471dc50 c4670654 c1809980 00000000
       c471dc60 c2f3f040 00000005 00000001 c471dc80 c02a7132 c591af64 00001eea
Call Trace:
 [<c037834c>] io_schedule+0x21/0x2e
 [<c014d505>] sync_page+0x38/0x43
 [<c0378581>] __wait_on_bit_lock+0x40/0x63
 [<c014d4b6>] __lock_page+0x54/0x5c
 [<c014da81>] do_generic_mapping_read+0x1dc/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016fc6e>] kernel_read+0x36/0x48
 [<c016fd32>] prepare_binprm+0xb2/0xdf
 [<c0171322>] do_execve+0xe6/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================
bash          D 0000004D     0  3012   2884 (NOTLB)
       c50d5a80 00000082 a21bfc35 0000004d 00000000 00000000 c180abc0 c2033dd4
       c50d5a70 c2f4f070 a21bfc35 0000004d 00000000 c2f4f184 c1809980 00000000
       c21167bc c47f0c80 c2033310 c22fc788 c5794e3c c2033dd4 00000002 0000216d
Call Trace:
 [<c01b64d9>] do_get_write_access+0x310/0x4f5
 [<c01b66d9>] journal_get_write_access+0x1b/0x2a
 [<c01b59ce>] __ext3_journal_get_write_access+0x19/0x3f
 [<c01aa5f6>] ext3_reserve_inode_write+0x53/0x6c
 [<c01aa62f>] ext3_mark_inode_dirty+0x20/0x37
 [<c01ad350>] ext3_dirty_inode+0x6b/0x6d
 [<c01868fb>] __mark_inode_dirty+0x2a/0x16d
 [<c017eacc>] touch_atime+0x84/0xd8
 [<c017499a>] __link_path_walk+0x893/0xca4
 [<c0174df1>] link_path_walk+0x46/0xc3
 [<c0175038>] do_path_lookup+0x86/0x1b0
 [<c0175ad0>] __path_lookup_intent_open+0x44/0x7f
 [<c0175b83>] path_lookup_open+0x21/0x27
 [<c016fd86>] open_exec+0x27/0xa2
 [<c01993a3>] load_elf_binary+0x1482/0x1acf
 [<c016fa1d>] search_binary_handler+0x6e/0x19f
 [<c0171386>] do_execve+0x14a/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================

Note that yum works on lvm on raid0 and git too, but on the another md volume. Both ext3s. Drivers are sata_promise and ata_piix (sata disk); CFQ scheduler. Using noop is no change (but seems to be harder to reproduce with it). I figured out that it probably happens when 2+ processes are on both "processors" (HT on P4) and are IO wait (multiload-applet shows red above the half).

Swap usage is 0 all the time.

regards,

Signature · 4 lines
http://www.fi.muni.cz/~xslaby/            Jiri Slaby
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
B674 9967 0407 CE62 ACC8  22A0 32CC 55C3 39D4 7A7E
#1 lore raw
Quoted 10 lines · On Mon, 30 Apr 2007 17:39:19 +0200 Jiri Slaby <[email protected]> wrote:

Hi,

I have a problem with higher disk loads (e.g. running git-log or yum update). Many processes end up in D state and system is unusable -- I'm not able to run anything but smooth mouse moving when this happens.

If I wait for a 20-30sec it becomes usable. This happens in 2.6.21-rc7-mm2 and also in 2007-04-28-05-06 broken-out snapshot. I think 2.6.21-rc6-mm1 worked fine, but I'm uncertain. If it is important, let me know to re-test.

It is important, but I doubt if retesting 2.6.21-rc6-mm1 will clarify things a lot.

Could you try switching to a different IO scheduler please? Anticipatory would suit.

Please keep a close eye on mainline, too. Wait for it to appear there :(

author
#2 lore raw
Quoted 14 lines · Andrew Morton
Quoted 10 lines · On Mon, 30 Apr 2007 17:39:19 +0200 Jiri Slaby <[email protected]> wrote:

Hi,

I have a problem with higher disk loads (e.g. running git-log or yum update). Many processes end up in D state and system is unusable -- I'm not able to run anything but smooth mouse moving when this happens.

If I wait for a 20-30sec it becomes usable. This happens in 2.6.21-rc7-mm2 and also in 2007-04-28-05-06 broken-out snapshot. I think 2.6.21-rc6-mm1 worked fine, but I'm uncertain. If it is important, let me know to re-test.

Quoted 5 lines

It is important, but I doubt if retesting 2.6.21-rc6-mm1 will clarify things a lot.

Could you try switching to a different IO scheduler please? Anticipatory would suit.

As I wrote below the sysrq-t, switch to noop didn't help, but it seems that it's harder to reproduce with that:

<cite it's_bad_to_write_anything_below_logs="true">
Note that yum works on lvm on raid0 and git too, but on the another md volume. Both ext3s. Drivers are sata_promise and ata_piix (sata disk); CFQ scheduler. Using noop is no change (but seems to be harder to reproduce with it). I figured out that it probably happens when 2+ processes are on both "processors" (HT on P4) and are IO wait (multiload-applet shows red above the half).

Swap usage is 0 all the time.
</cite>

Quoted 1 line

Please keep a close eye on mainline, too. Wait for it to appear there :(

Ok, I'll try to play with that...

thanks,

Signature · 4 lines
http://www.fi.muni.cz/~xslaby/            Jiri Slaby
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
B674 9967 0407 CE62 ACC8  22A0 32CC 55C3 39D4 7A7E
#3 lore raw
Quoted 25 lines · On Mon, 30 Apr 2007 20:14:05 +0200 "Jiri Slaby" <[email protected]> wrote:
Quoted 9 lines
Quoted 8 lines

I have a problem with higher disk loads (e.g. running git-log or yum update). Many processes end up in D state and system is unusable -- I'm not able to run anything but smooth mouse moving when this happens.

If I wait for a 20-30sec it becomes usable. This happens in 2.6.21-rc7-mm2 and also in 2007-04-28-05-06 broken-out snapshot. I think 2.6.21-rc6-mm1 worked fine, but I'm uncertain. If it is important, let me know to re-test.

Quoted 5 lines

It is important, but I doubt if retesting 2.6.21-rc6-mm1 will clarify things a lot.

Could you try switching to a different IO scheduler please? Anticipatory would suit.

As I wrote below the sysrq-t, switch to noop didn't help, but it seems that it's harder to reproduce with that:

<cite it's_bad_to_write_anything_below_logs="true">
Note that yum works on lvm on raid0 and git too, but on the another md volume. Both ext3s. Drivers are sata_promise and ata_piix (sata disk); CFQ scheduler. Using noop is no change (but seems to be harder to reproduce with it). I figured out that it probably happens when 2+ processes are on both "processors" (HT on P4) and are IO wait (multiload-applet shows red above the half).

Quoted 2 lines

Swap usage is 0 all the time.
</cite>

My comprehension skills on Monday morning are even less than usual ;)

I would check the anticipatory scheduler as well, please. I don't know what no-op would do with a workload like that, but it probably isn't very good.

You appear to believe that it's related to the CPU scheduler? That's a bit unexpected - it sounds more like a VFS/IO thing? But stranger things have happened.

I guess it's time to end the staircase experiment in -mm.
http://userweb.kernel.org/~akpm/js.bz2 is my current rollup (against 2.6.21) minus staircase and related things. Pretty please.

author
#4 lore raw

Andrew Morton napsal(a):

Quoted 5 lines

I would check the anticipatory scheduler as well, please. I don't know what no-op would do with a workload like that, but it probably isn't very good.

You appear to believe that it's related to the CPU scheduler?

Oh, no. I have really no idea, what may cause this :).

Quoted 3 lines

That's a bit
unexpected - it sounds more like a VFS/IO thing? But stranger things have happened.

I think so.

Quoted 3 lines

I guess it's time to end the staircase experiment in -mm.
http://userweb.kernel.org/~akpm/js.bz2 is my current rollup (against 2.6.21) minus staircase and related things. Pretty please.

Anticipatory + -js is no change. Going to try vanilla and in both cases whether it works or not, I'll bisect either -mm or vanilla.

regards,

Signature · 4 lines
http://www.fi.muni.cz/~xslaby/            Jiri Slaby
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
B674 9967 0407 CE62 ACC8  22A0 32CC 55C3 39D4 7A7E
author
#5 lore raw
In reply to Jiri Slaby

Jiri Slaby napsal(a):

Quoted 136 lines

Hi,

I have a problem with higher disk loads (e.g. running git-log or yum update). Many processes end up in D state and system is unusable -- I'm not able to run anything but smooth mouse moving when this happens.

If I wait for a 20-30sec it becomes usable. This happens in 2.6.21-rc7-mm2 and also in 2007-04-28-05-06 broken-out snapshot. I think 2.6.21-rc6-mm1 worked fine, but I'm uncertain. If it is important, let me know to re-test.

sysrq-t:

yum D 0000004C 0 2976 2955 (NOTLB)

       c455bd00 00200082 8c68ea9e 0000004c 00000000 00000000 c455bcdc c455bc9c
       c455bc9c c2d6a580 8c68ea9e 0000004c c455bcc0 c2d6a694 c1809980 00000000
       c455bcd0 c4640c80 000036a0 00000001 c455bcf0 c02a7132 c3682164 00001cde
Call Trace:
 [<c037834c>] io_schedule+0x21/0x2e
 [<c014d505>] sync_page+0x38/0x43
 [<c0378581>] __wait_on_bit_lock+0x40/0x63
 [<c014d4b6>] __lock_page+0x54/0x5c
 [<c014da81>] do_generic_mapping_read+0x1dc/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016d02c>] sys_pread64+0x64/0x68
 [<c0103ffc>] syscall_call+0x7/0xb
 [<47176012>] 0x47176012
 =======================
xterm         S 00000051     0  2980      1 (NOTLB)
       c4678ae0 00000082 b2fbf0ce 00000051 00000000 00000000 00000000 00000000
       c4678b30 c469d540 b2fbf0ce 00000051 c4678ab0 c469d654 c1813980 00000001
       c4678ad0 c47f0e40 c4678b00 00000286 c4678ae0 c012c077 00000001 00003286
Call Trace:
 [<c03784ad>] schedule_timeout+0x44/0xa4
 [<c0177ee3>] do_select+0x46d/0x55b
 [<c017816f>] core_sys_select+0x19e/0x2c0
 [<c01786f3>] sys_select+0xd3/0x18d
 [<c0103ffc>] syscall_call+0x7/0xb
 [<47180f98>] 0x47180f98
 =======================
bash          S 0000004A     0  2982   2980 (NOTLB)
       c50b3e80 00000086 ccf4cc7e 0000004a 00000000 c021bed9 00000000 c45c0030
       c50b3e30 c45c0030 ccf4cc7e 0000004a c50b3e50 c45c0144 c1809980 00000000
       c1809e44 c4517900 00000000 000000b3 c50b3e90 c014f841 c477cb40 c2d79000
Call Trace:
 [<c03784d3>] schedule_timeout+0x6a/0xa4
 [<c0221960>] read_chan+0x1b9/0x5b9
 [<c021e48f>] tty_read+0x75/0xaa
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016cf3d>] sys_read+0x3d/0x64
 [<c0103ffc>] syscall_call+0x7/0xb
 [<4717883e>] 0x4717883e
 =======================
metacity      S 00000050     0  3005   2429 (NOTLB)
       c2fd5bb0 00000086 5205656d 00000050 00000000 00000000 00000000 c441c51c
       00000246 c45c0540 5205656d 00000050 c2fd5b80 c45c0654 c1809980 00000000
       c1813e44 c27f4900 00002cb8 00000246 c2fd5ba0 c0135a80 c2fd5ba8 00002cb2
Call Trace:
 [<c03784d3>] schedule_timeout+0x6a/0xa4
 [<c0177905>] do_sys_poll+0x33f/0x46d
 [<c0177a74>] sys_poll+0x41/0x43
 [<c0103ffc>] syscall_call+0x7/0xb
 [<4717e3a6>] 0x4717e3a6
 =======================
ccpd          D 0000004C     0  3009   2010 (NOTLB)
       c50abbb0 00000082 f08ef585 0000004c 00000000 00000000 c180abc0 c22fc788
       c50abba0 c505d070 f08ef585 0000004c 00000000 c505d184 c1809980 00000000
       c21167f0 c2fc6740 c5794e3c c31eff74 c5794310 c22fc788 00000002 00001e64
Call Trace:
 [<c01b64d9>] do_get_write_access+0x310/0x4f5
 [<c01b66d9>] journal_get_write_access+0x1b/0x2a
 [<c01b59ce>] __ext3_journal_get_write_access+0x19/0x3f
 [<c01aa5f6>] ext3_reserve_inode_write+0x53/0x6c
 [<c01aa62f>] ext3_mark_inode_dirty+0x20/0x37
 [<c01ad350>] ext3_dirty_inode+0x6b/0x6d
 [<c01868fb>] __mark_inode_dirty+0x2a/0x16d
 [<c017eacc>] touch_atime+0x84/0xd8
 [<c014dd08>] do_generic_mapping_read+0x463/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016fc6e>] kernel_read+0x36/0x48
 [<c016fd32>] prepare_binprm+0xb2/0xdf
 [<c0171322>] do_execve+0xe6/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================
bash          D 0000004D     0  3011   2859 (NOTLB)
       c471dc90 00000082 08f8373c 0000004d 00000000 00000000 c471dc30 c471dc2c
       c471dc2c c4670540 08f8373c 0000004d c471dc50 c4670654 c1809980 00000000
       c471dc60 c2f3f040 00000005 00000001 c471dc80 c02a7132 c591af64 00001eea
Call Trace:
 [<c037834c>] io_schedule+0x21/0x2e
 [<c014d505>] sync_page+0x38/0x43
 [<c0378581>] __wait_on_bit_lock+0x40/0x63
 [<c014d4b6>] __lock_page+0x54/0x5c
 [<c014da81>] do_generic_mapping_read+0x1dc/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016fc6e>] kernel_read+0x36/0x48
 [<c016fd32>] prepare_binprm+0xb2/0xdf
 [<c0171322>] do_execve+0xe6/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================
bash          D 0000004D     0  3012   2884 (NOTLB)
       c50d5a80 00000082 a21bfc35 0000004d 00000000 00000000 c180abc0 c2033dd4
       c50d5a70 c2f4f070 a21bfc35 0000004d 00000000 c2f4f184 c1809980 00000000
       c21167bc c47f0c80 c2033310 c22fc788 c5794e3c c2033dd4 00000002 0000216d
Call Trace:
 [<c01b64d9>] do_get_write_access+0x310/0x4f5
 [<c01b66d9>] journal_get_write_access+0x1b/0x2a
 [<c01b59ce>] __ext3_journal_get_write_access+0x19/0x3f
 [<c01aa5f6>] ext3_reserve_inode_write+0x53/0x6c
 [<c01aa62f>] ext3_mark_inode_dirty+0x20/0x37
 [<c01ad350>] ext3_dirty_inode+0x6b/0x6d
 [<c01868fb>] __mark_inode_dirty+0x2a/0x16d
 [<c017eacc>] touch_atime+0x84/0xd8
 [<c017499a>] __link_path_walk+0x893/0xca4
 [<c0174df1>] link_path_walk+0x46/0xc3
 [<c0175038>] do_path_lookup+0x86/0x1b0
 [<c0175ad0>] __path_lookup_intent_open+0x44/0x7f
 [<c0175b83>] path_lookup_open+0x21/0x27
 [<c016fd86>] open_exec+0x27/0xa2
 [<c01993a3>] load_elf_binary+0x1482/0x1acf
 [<c016fa1d>] search_binary_handler+0x6e/0x19f
 [<c0171386>] do_execve+0x14a/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================
Quoted 7 lines

Note that yum works on lvm on raid0 and git too, but on the another md volume. Both ext3s. Drivers are sata_promise and ata_piix (sata disk); CFQ scheduler. Using noop is no change (but seems to be harder to reproduce with it). I figured out that it probably happens when 2+ processes are on both "processors" (HT on P4) and are IO wait (multiload-applet shows red above the half).

Swap usage is 0 all the time.

I'm able to reproduce this in the latest git (dc87c3985e9b442c). Going to bisect.

regards,

Signature · 4 lines
http://www.fi.muni.cz/~xslaby/            Jiri Slaby
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
B674 9967 0407 CE62 ACC8  22A0 32CC 55C3 39D4 7A7E
author
#6 lore raw
Cc Mikael Pettersson <[email protected]>
Cc Jeff Garzik <[email protected]>

Jiri Slaby napsal(a):

Quoted 145 lines

Jiri Slaby napsal(a):

Quoted 142 lines

Hi,

I have a problem with higher disk loads (e.g. running git-log or yum update). Many processes end up in D state and system is unusable -- I'm not able to run anything but smooth mouse moving when this happens.

If I wait for a 20-30sec it becomes usable. This happens in 2.6.21-rc7-mm2 and also in 2007-04-28-05-06 broken-out snapshot. I think 2.6.21-rc6-mm1 worked fine, but I'm uncertain. If it is important, let me know to re-test.

sysrq-t:

yum D 0000004C 0 2976 2955 (NOTLB)

       c455bd00 00200082 8c68ea9e 0000004c 00000000 00000000 c455bcdc c455bc9c
       c455bc9c c2d6a580 8c68ea9e 0000004c c455bcc0 c2d6a694 c1809980 00000000
       c455bcd0 c4640c80 000036a0 00000001 c455bcf0 c02a7132 c3682164 00001cde
Call Trace:
 [<c037834c>] io_schedule+0x21/0x2e
 [<c014d505>] sync_page+0x38/0x43
 [<c0378581>] __wait_on_bit_lock+0x40/0x63
 [<c014d4b6>] __lock_page+0x54/0x5c
 [<c014da81>] do_generic_mapping_read+0x1dc/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016d02c>] sys_pread64+0x64/0x68
 [<c0103ffc>] syscall_call+0x7/0xb
 [<47176012>] 0x47176012
 =======================
xterm         S 00000051     0  2980      1 (NOTLB)
       c4678ae0 00000082 b2fbf0ce 00000051 00000000 00000000 00000000 00000000
       c4678b30 c469d540 b2fbf0ce 00000051 c4678ab0 c469d654 c1813980 00000001
       c4678ad0 c47f0e40 c4678b00 00000286 c4678ae0 c012c077 00000001 00003286
Call Trace:
 [<c03784ad>] schedule_timeout+0x44/0xa4
 [<c0177ee3>] do_select+0x46d/0x55b
 [<c017816f>] core_sys_select+0x19e/0x2c0
 [<c01786f3>] sys_select+0xd3/0x18d
 [<c0103ffc>] syscall_call+0x7/0xb
 [<47180f98>] 0x47180f98
 =======================
bash          S 0000004A     0  2982   2980 (NOTLB)
       c50b3e80 00000086 ccf4cc7e 0000004a 00000000 c021bed9 00000000 c45c0030
       c50b3e30 c45c0030 ccf4cc7e 0000004a c50b3e50 c45c0144 c1809980 00000000
       c1809e44 c4517900 00000000 000000b3 c50b3e90 c014f841 c477cb40 c2d79000
Call Trace:
 [<c03784d3>] schedule_timeout+0x6a/0xa4
 [<c0221960>] read_chan+0x1b9/0x5b9
 [<c021e48f>] tty_read+0x75/0xaa
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016cf3d>] sys_read+0x3d/0x64
 [<c0103ffc>] syscall_call+0x7/0xb
 [<4717883e>] 0x4717883e
 =======================
metacity      S 00000050     0  3005   2429 (NOTLB)
       c2fd5bb0 00000086 5205656d 00000050 00000000 00000000 00000000 c441c51c
       00000246 c45c0540 5205656d 00000050 c2fd5b80 c45c0654 c1809980 00000000
       c1813e44 c27f4900 00002cb8 00000246 c2fd5ba0 c0135a80 c2fd5ba8 00002cb2
Call Trace:
 [<c03784d3>] schedule_timeout+0x6a/0xa4
 [<c0177905>] do_sys_poll+0x33f/0x46d
 [<c0177a74>] sys_poll+0x41/0x43
 [<c0103ffc>] syscall_call+0x7/0xb
 [<4717e3a6>] 0x4717e3a6
 =======================
ccpd          D 0000004C     0  3009   2010 (NOTLB)
       c50abbb0 00000082 f08ef585 0000004c 00000000 00000000 c180abc0 c22fc788
       c50abba0 c505d070 f08ef585 0000004c 00000000 c505d184 c1809980 00000000
       c21167f0 c2fc6740 c5794e3c c31eff74 c5794310 c22fc788 00000002 00001e64
Call Trace:
 [<c01b64d9>] do_get_write_access+0x310/0x4f5
 [<c01b66d9>] journal_get_write_access+0x1b/0x2a
 [<c01b59ce>] __ext3_journal_get_write_access+0x19/0x3f
 [<c01aa5f6>] ext3_reserve_inode_write+0x53/0x6c
 [<c01aa62f>] ext3_mark_inode_dirty+0x20/0x37
 [<c01ad350>] ext3_dirty_inode+0x6b/0x6d
 [<c01868fb>] __mark_inode_dirty+0x2a/0x16d
 [<c017eacc>] touch_atime+0x84/0xd8
 [<c014dd08>] do_generic_mapping_read+0x463/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016fc6e>] kernel_read+0x36/0x48
 [<c016fd32>] prepare_binprm+0xb2/0xdf
 [<c0171322>] do_execve+0xe6/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================
bash          D 0000004D     0  3011   2859 (NOTLB)
       c471dc90 00000082 08f8373c 0000004d 00000000 00000000 c471dc30 c471dc2c
       c471dc2c c4670540 08f8373c 0000004d c471dc50 c4670654 c1809980 00000000
       c471dc60 c2f3f040 00000005 00000001 c471dc80 c02a7132 c591af64 00001eea
Call Trace:
 [<c037834c>] io_schedule+0x21/0x2e
 [<c014d505>] sync_page+0x38/0x43
 [<c0378581>] __wait_on_bit_lock+0x40/0x63
 [<c014d4b6>] __lock_page+0x54/0x5c
 [<c014da81>] do_generic_mapping_read+0x1dc/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016fc6e>] kernel_read+0x36/0x48
 [<c016fd32>] prepare_binprm+0xb2/0xdf
 [<c0171322>] do_execve+0xe6/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================
bash          D 0000004D     0  3012   2884 (NOTLB)
       c50d5a80 00000082 a21bfc35 0000004d 00000000 00000000 c180abc0 c2033dd4
       c50d5a70 c2f4f070 a21bfc35 0000004d 00000000 c2f4f184 c1809980 00000000
       c21167bc c47f0c80 c2033310 c22fc788 c5794e3c c2033dd4 00000002 0000216d
Call Trace:
 [<c01b64d9>] do_get_write_access+0x310/0x4f5
 [<c01b66d9>] journal_get_write_access+0x1b/0x2a
 [<c01b59ce>] __ext3_journal_get_write_access+0x19/0x3f
 [<c01aa5f6>] ext3_reserve_inode_write+0x53/0x6c
 [<c01aa62f>] ext3_mark_inode_dirty+0x20/0x37
 [<c01ad350>] ext3_dirty_inode+0x6b/0x6d
 [<c01868fb>] __mark_inode_dirty+0x2a/0x16d
 [<c017eacc>] touch_atime+0x84/0xd8
 [<c017499a>] __link_path_walk+0x893/0xca4
 [<c0174df1>] link_path_walk+0x46/0xc3
 [<c0175038>] do_path_lookup+0x86/0x1b0
 [<c0175ad0>] __path_lookup_intent_open+0x44/0x7f
 [<c0175b83>] path_lookup_open+0x21/0x27
 [<c016fd86>] open_exec+0x27/0xa2
 [<c01993a3>] load_elf_binary+0x1482/0x1acf
 [<c016fa1d>] search_binary_handler+0x6e/0x19f
 [<c0171386>] do_execve+0x14a/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================

Note that yum works on lvm on raid0 and git too, but on the another md volume. Both ext3s. Drivers are sata_promise and ata_piix (sata disk); CFQ scheduler. Using noop is no change (but seems to be harder to reproduce with it). I figured out that it probably happens when 2+ processes are on both "processors" (HT on P4) and are IO wait (multiload-applet shows red above the half).

Quoted 3 lines
Quoted 1 line

Swap usage is 0 all the time.

I'm able to reproduce this in the latest git (dc87c3985e9b442c). Going to bisect.

Is it possible, that
Commit: 176efb054422bffe6b5a34194ffad134366c7f7e
Author: Mikael Pettersson <[email protected]> Wed, 14 Mar 2007 09:51:35 +0100

sata_promise: decode and report error reasons

This patch adds much needed error reason decoding and reporting to sata_promise. It's simplistic but should log all relevant error info the controller provides.

causes this? When I change this:

drivers/ata/sata_promise.c +1 -3
index f56549b..a0024ae 100644
@@ -668,10 +668,8 @@ static inline unsigned int pdc_host_intr( struct ata_port *ap,
        else
                err_mask &= ~PDC2_ERR_MASK;
        port_status = readl(port_mmio + PDC_GLOBAL_CTL);
-       if (unlikely(port_status & err_mask)) {
+       if (unlikely(port_status & err_mask))
                pdc_error_intr(ap, qc, port_status, err_mask);
-               return 1;
-       }
 
        switch (qc->tf.protocol) {
        case ATA_PROT_DMA:

the problem disappears.

regards,

Signature · 4 lines
http://www.fi.muni.cz/~xslaby/            Jiri Slaby
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
B674 9967 0407 CE62 ACC8  22A0 32CC 55C3 39D4 7A7E
author
#7 lore raw

Jiri Slaby napsal(a):

Quoted 183 lines
Cc Mikael Pettersson <[email protected]>
Cc Jeff Garzik <[email protected]>

Jiri Slaby napsal(a):

Quoted 139 lines

Jiri Slaby napsal(a):

Quoted 136 lines

Hi,

I have a problem with higher disk loads (e.g. running git-log or yum update). Many processes end up in D state and system is unusable -- I'm not able to run anything but smooth mouse moving when this happens.

If I wait for a 20-30sec it becomes usable. This happens in 2.6.21-rc7-mm2 and also in 2007-04-28-05-06 broken-out snapshot. I think 2.6.21-rc6-mm1 worked fine, but I'm uncertain. If it is important, let me know to re-test.

sysrq-t:

yum D 0000004C 0 2976 2955 (NOTLB)

       c455bd00 00200082 8c68ea9e 0000004c 00000000 00000000 c455bcdc c455bc9c
       c455bc9c c2d6a580 8c68ea9e 0000004c c455bcc0 c2d6a694 c1809980 00000000
       c455bcd0 c4640c80 000036a0 00000001 c455bcf0 c02a7132 c3682164 00001cde
Call Trace:
 [<c037834c>] io_schedule+0x21/0x2e
 [<c014d505>] sync_page+0x38/0x43
 [<c0378581>] __wait_on_bit_lock+0x40/0x63
 [<c014d4b6>] __lock_page+0x54/0x5c
 [<c014da81>] do_generic_mapping_read+0x1dc/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016d02c>] sys_pread64+0x64/0x68
 [<c0103ffc>] syscall_call+0x7/0xb
 [<47176012>] 0x47176012
 =======================
xterm         S 00000051     0  2980      1 (NOTLB)
       c4678ae0 00000082 b2fbf0ce 00000051 00000000 00000000 00000000 00000000
       c4678b30 c469d540 b2fbf0ce 00000051 c4678ab0 c469d654 c1813980 00000001
       c4678ad0 c47f0e40 c4678b00 00000286 c4678ae0 c012c077 00000001 00003286
Call Trace:
 [<c03784ad>] schedule_timeout+0x44/0xa4
 [<c0177ee3>] do_select+0x46d/0x55b
 [<c017816f>] core_sys_select+0x19e/0x2c0
 [<c01786f3>] sys_select+0xd3/0x18d
 [<c0103ffc>] syscall_call+0x7/0xb
 [<47180f98>] 0x47180f98
 =======================
bash          S 0000004A     0  2982   2980 (NOTLB)
       c50b3e80 00000086 ccf4cc7e 0000004a 00000000 c021bed9 00000000 c45c0030
       c50b3e30 c45c0030 ccf4cc7e 0000004a c50b3e50 c45c0144 c1809980 00000000
       c1809e44 c4517900 00000000 000000b3 c50b3e90 c014f841 c477cb40 c2d79000
Call Trace:
 [<c03784d3>] schedule_timeout+0x6a/0xa4
 [<c0221960>] read_chan+0x1b9/0x5b9
 [<c021e48f>] tty_read+0x75/0xaa
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016cf3d>] sys_read+0x3d/0x64
 [<c0103ffc>] syscall_call+0x7/0xb
 [<4717883e>] 0x4717883e
 =======================
metacity      S 00000050     0  3005   2429 (NOTLB)
       c2fd5bb0 00000086 5205656d 00000050 00000000 00000000 00000000 c441c51c
       00000246 c45c0540 5205656d 00000050 c2fd5b80 c45c0654 c1809980 00000000
       c1813e44 c27f4900 00002cb8 00000246 c2fd5ba0 c0135a80 c2fd5ba8 00002cb2
Call Trace:
 [<c03784d3>] schedule_timeout+0x6a/0xa4
 [<c0177905>] do_sys_poll+0x33f/0x46d
 [<c0177a74>] sys_poll+0x41/0x43
 [<c0103ffc>] syscall_call+0x7/0xb
 [<4717e3a6>] 0x4717e3a6
 =======================
ccpd          D 0000004C     0  3009   2010 (NOTLB)
       c50abbb0 00000082 f08ef585 0000004c 00000000 00000000 c180abc0 c22fc788
       c50abba0 c505d070 f08ef585 0000004c 00000000 c505d184 c1809980 00000000
       c21167f0 c2fc6740 c5794e3c c31eff74 c5794310 c22fc788 00000002 00001e64
Call Trace:
 [<c01b64d9>] do_get_write_access+0x310/0x4f5
 [<c01b66d9>] journal_get_write_access+0x1b/0x2a
 [<c01b59ce>] __ext3_journal_get_write_access+0x19/0x3f
 [<c01aa5f6>] ext3_reserve_inode_write+0x53/0x6c
 [<c01aa62f>] ext3_mark_inode_dirty+0x20/0x37
 [<c01ad350>] ext3_dirty_inode+0x6b/0x6d
 [<c01868fb>] __mark_inode_dirty+0x2a/0x16d
 [<c017eacc>] touch_atime+0x84/0xd8
 [<c014dd08>] do_generic_mapping_read+0x463/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016fc6e>] kernel_read+0x36/0x48
 [<c016fd32>] prepare_binprm+0xb2/0xdf
 [<c0171322>] do_execve+0xe6/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================
bash          D 0000004D     0  3011   2859 (NOTLB)
       c471dc90 00000082 08f8373c 0000004d 00000000 00000000 c471dc30 c471dc2c
       c471dc2c c4670540 08f8373c 0000004d c471dc50 c4670654 c1809980 00000000
       c471dc60 c2f3f040 00000005 00000001 c471dc80 c02a7132 c591af64 00001eea
Call Trace:
 [<c037834c>] io_schedule+0x21/0x2e
 [<c014d505>] sync_page+0x38/0x43
 [<c0378581>] __wait_on_bit_lock+0x40/0x63
 [<c014d4b6>] __lock_page+0x54/0x5c
 [<c014da81>] do_generic_mapping_read+0x1dc/0x57e
 [<c014fc84>] generic_file_aio_read+0xc9/0x1b5
 [<c016c31c>] do_sync_read+0xd0/0x106
 [<c016cada>] vfs_read+0x89/0x11d
 [<c016fc6e>] kernel_read+0x36/0x48
 [<c016fd32>] prepare_binprm+0xb2/0xdf
 [<c0171322>] do_execve+0xe6/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================
bash          D 0000004D     0  3012   2884 (NOTLB)
       c50d5a80 00000082 a21bfc35 0000004d 00000000 00000000 c180abc0 c2033dd4
       c50d5a70 c2f4f070 a21bfc35 0000004d 00000000 c2f4f184 c1809980 00000000
       c21167bc c47f0c80 c2033310 c22fc788 c5794e3c c2033dd4 00000002 0000216d
Call Trace:
 [<c01b64d9>] do_get_write_access+0x310/0x4f5
 [<c01b66d9>] journal_get_write_access+0x1b/0x2a
 [<c01b59ce>] __ext3_journal_get_write_access+0x19/0x3f
 [<c01aa5f6>] ext3_reserve_inode_write+0x53/0x6c
 [<c01aa62f>] ext3_mark_inode_dirty+0x20/0x37
 [<c01ad350>] ext3_dirty_inode+0x6b/0x6d
 [<c01868fb>] __mark_inode_dirty+0x2a/0x16d
 [<c017eacc>] touch_atime+0x84/0xd8
 [<c017499a>] __link_path_walk+0x893/0xca4
 [<c0174df1>] link_path_walk+0x46/0xc3
 [<c0175038>] do_path_lookup+0x86/0x1b0
 [<c0175ad0>] __path_lookup_intent_open+0x44/0x7f
 [<c0175b83>] path_lookup_open+0x21/0x27
 [<c016fd86>] open_exec+0x27/0xa2
 [<c01993a3>] load_elf_binary+0x1482/0x1acf
 [<c016fa1d>] search_binary_handler+0x6e/0x19f
 [<c0171386>] do_execve+0x14a/0x1e1
 [<c0102715>] sys_execve+0x2e/0x7f
 [<c0103ffc>] syscall_call+0x7/0xb
 [<471474da>] 0x471474da
 =======================
Quoted 8 lines
Quoted 7 lines

Note that yum works on lvm on raid0 and git too, but on the another md volume. Both ext3s. Drivers are sata_promise and ata_piix (sata disk); CFQ scheduler. Using noop is no change (but seems to be harder to reproduce with it). I figured out that it probably happens when 2+ processes are on both "processors" (HT on P4) and are IO wait (multiload-applet shows red above the half).

Swap usage is 0 all the time.

I'm able to reproduce this in the latest git (dc87c3985e9b442c). Going to bisect.

Is it possible, that
Commit: 176efb054422bffe6b5a34194ffad134366c7f7e
Author: Mikael Pettersson <[email protected]> Wed, 14 Mar 2007 09:51:35 +0100

sata_promise: decode and report error reasons

This patch adds much needed error reason decoding and reporting to sata_promise. It's simplistic but should log all relevant error info the controller provides.

causes this? When I change this:

drivers/ata/sata_promise.c +1 -3
index f56549b..a0024ae 100644
@@ -668,10 +668,8 @@ static inline unsigned int pdc_host_intr( struct ata_port *ap,
        else
                err_mask &= ~PDC2_ERR_MASK;
        port_status = readl(port_mmio + PDC_GLOBAL_CTL);
-       if (unlikely(port_status & err_mask)) {
+       if (unlikely(port_status & err_mask))
                pdc_error_intr(ap, qc, port_status, err_mask);
-               return 1;
-       }
 
        switch (qc->tf.protocol) {
        case ATA_PROT_DMA:
Quoted 1 line

the problem disappears.

Actually changes:
ata6.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 frozen ata6.00: (port_status 0x20080000)
ata6.00: cmd c8/00:08:03:d3:61/00:00:00:00:00/e0 tag 0 cdb 0x0 data 4096 in

         res 40/00:01:01:4f:c2/00:00:00:00:00/00 Emask 0x6 (timeout)

ata6: soft resetting port
ata6: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
ata6.00: ata_hpa_resize 1: sectors = 156301488, hpa_sectors = 156301488 ata6.00: ata_hpa_resize 1: sectors = 156301488, hpa_sectors = 156301488 ata6.00: configured for UDMA/133
ata6: EH complete
sd 5:0:0:0: [sdc] 156301488 512-byte hardware sectors (80026 MB)
sd 5:0:0:0: [sdc] Write Protect is off
sd 5:0:0:0: [sdc] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA

to
ata5.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 ata5.00: (port_status 0x20080000)
ata5.00: cmd c8/00:08:bf:cd:4b/00:00:00:00:00/e0 tag 0 cdb 0x0 data 4096 in

         res 50/00:00:c6:cd:4b/00:00:00:00:00/e0 Emask 0x2 (HSM violation)

ata5: soft resetting port
ata5: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
ata5.00: ata_hpa_resize 1: sectors = 156301488, hpa_sectors = 156301488 ata5.00: ata_hpa_resize 1: sectors = 156301488, hpa_sectors = 156301488 ata5.00: configured for UDMA/133
ata5: EH complete
sd 4:0:0:0: [sdb] 156301488 512-byte hardware sectors (80026 MB)
sd 4:0:0:0: [sdb] Write Protect is off
sd 4:0:0:0: [sdb] Mode Sense: 00 3a 00 00
sd 4:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA

I.e. no freezing of ports...

regards,

Signature · 4 lines
http://www.fi.muni.cz/~xslaby/            Jiri Slaby
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
B674 9967 0407 CE62 ACC8  22A0 32CC 55C3 39D4 7A7E