public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
* Exaggerated swap usage
@ 2002-11-29 11:54 Javier Marcet
  2002-11-29 12:20 ` Christer Nilsson
  2002-11-29 16:31 ` Rik van Riel
  0 siblings, 2 replies; 39+ messages in thread
From: Javier Marcet @ 2002-11-29 11:54 UTC (permalink / raw)
  To: linux-kernel

[-- Attachment #1: Type: text/plain, Size: 1411 bytes --]


Forgive me if I don't provide enough information just yet, or am not
clear enough. I simply don't know what setting to tweak.

I'll explain.
In recent 2.4.20 pre and rc kernels ( I tend to use the ac branch ), I
had notice my system, when using X mainly, got terribly slow after some
use. It surprised me that when I tried 2.5.47 this did not happen at
all, since I thought my problem was a lack of memory - the system has
384MB -.
Hence I tried to find where the difference was. What I found is that
2.4.20 kernels - 2.4.19 does the same -, was swapping just too much,
while there was a lot free memory on the system, cached but free.
I disabled all swap and it suddenly began to work smoothly again, yet
with the random kills when memory was a scarce resource on the system.
I've tried different sysctl's vm.overcommit settings but the result is
the same.

I also found a 2.4.x kernel which did not show this behavior, WOLK, in
any version I tried.

Could you please point me toward something I can try tweaking, or some
documentation to read which explains what I can change, unless it's some
kind of kernel problem?

BTW, aa kernels behaved somewhat better on this, only that the last one
I tried -rc2aa1- had some stability problems.

I can provide you with dmesg, /proc/meminfo or whatever might be useful.

Thanks in advance :)


-- 
Javier Marcet <jmarcet@pobox.com>

[-- Attachment #2: Type: application/pgp-signature, Size: 197 bytes --]

^ permalink raw reply	[flat|nested] 39+ messages in thread
* RE: Exaggerated swap usage
@ 2002-11-29 15:28 Randal, Phil
  2002-11-29 16:28 ` Rik van Riel
  0 siblings, 1 reply; 39+ messages in thread
From: Randal, Phil @ 2002-11-29 15:28 UTC (permalink / raw)
  To: 'Javier Marcet', linux-kernel

Same thing happens with RedHat 8.0's latest 2.4.18-18 kernel.
Box has been up for almost 8 days.

top:

Mem:  1031036K av, 1021140K used,    9896K free,       0K shrd,   80560K
buff
Swap: 1052216K av,    5064K used, 1047152K free                  627808K
cached

vmstat:

   procs                      memory    swap          io     system
cpu
 r  b  w   swpd   free   buff  cache  si  so    bi    bo   in    cs  us  sy
id
 0  0  0   5064  10192  80860 626932   0   0     2    21    3    56   0   0
36

Swapping in these circumstances shows a pathological reluctance to shed
cached pages.

Not critical, but hardly optimal behaviour.  Or is it?

Phil
---------------------------------------------
Phil Randal
Network Engineer
Herefordshire Council
Hereford, UK 

> -----Original Message-----
> From: Javier Marcet [mailto:jmarcet@pobox.com]
> Sent: 29 November 2002 11:54
> To: linux-kernel@vger.kernel.org
> Subject: Exaggerated swap usage
> 
> 
> 
> Forgive me if I don't provide enough information just yet, or am not
> clear enough. I simply don't know what setting to tweak.
> 
> I'll explain.
> In recent 2.4.20 pre and rc kernels ( I tend to use the ac branch ), I
> had notice my system, when using X mainly, got terribly slow 
> after some
> use. It surprised me that when I tried 2.5.47 this did not happen at
> all, since I thought my problem was a lack of memory - the system has
> 384MB -.
> Hence I tried to find where the difference was. What I found is that
> 2.4.20 kernels - 2.4.19 does the same -, was swapping just too much,
> while there was a lot free memory on the system, cached but free.
> I disabled all swap and it suddenly began to work smoothly again, yet
> with the random kills when memory was a scarce resource on the system.
> I've tried different sysctl's vm.overcommit settings but the result is
> the same.
> 
> I also found a 2.4.x kernel which did not show this behavior, WOLK, in
> any version I tried.
> 
> Could you please point me toward something I can try tweaking, or some
> documentation to read which explains what I can change, 
> unless it's some
> kind of kernel problem?
> 
> BTW, aa kernels behaved somewhat better on this, only that 
> the last one
> I tried -rc2aa1- had some stability problems.
> 
> I can provide you with dmesg, /proc/meminfo or whatever might 
> be useful.
> 
> Thanks in advance :)
> 
> 
> -- 
> Javier Marcet <jmarcet@pobox.com>
> 

^ permalink raw reply	[flat|nested] 39+ messages in thread
* Re: Exaggerated swap usage
@ 2002-12-02 23:59 Marc-Christian Petersen
  2002-12-03  0:59 ` Andrea Arcangeli
  0 siblings, 1 reply; 39+ messages in thread
From: Marc-Christian Petersen @ 2002-12-02 23:59 UTC (permalink / raw)
  To: linux-kernel; +Cc: Andrea Arcangeli, Andrew Clayton, Javier Marcet

Hi Andrea,

> > ok, now it's clear what the problem is. there are inuse-dirty inodes
> > that triggers a deadlock in the schedule-capable
> > try_to_sync_unused_inodes of 2.4.20rc2aa1 (that avoided me to backout an
> > otherwise corrupt lowlatency fix). It can trigger only in UP,
> > in SMP the other cpu can always run kupdate that will flush all dirty
> > inodes, so it would lockup one cpu as worse for 2.5 sec, this is
> > probably why I couldn't reproduce it, I assume all of you reproducing
> > the deadlock were running on an UP machine (doesn't matter if the kernel
> Correct (for me anyways). 
ok, deadlock is gone, instead I have EXT3-fs corruption (non data=journal 
mode, just ordered) like this:


Dec  3 00:25:39 codeman kernel: EXT3-fs error (device ide0(3,9)): 
ext3_free_blocks: Freeing blocks not in datazone - block = 1530182
, count = 1
Dec  3 00:25:39 codeman kernel: Aborting journal on device ide0(3,9).
Dec  3 00:25:39 codeman kernel: ext3_free_blocks: aborting transaction: 
Journal has aborted in __ext3_journal_get_undo_access<2>EXT3
-fs error (device ide0(3,9)) in ext3_free_blocks: Journal has aborted
Dec  3 00:25:39 codeman kernel: ext3_reserve_inode_write: aborting 
transaction: Journal has aborted in __ext3_journal_get_write_acce
ss<2>EXT3-fs error (device ide0(3,9)) in ext3_reserve_inode_write: Journal has 
aborted
Dec  3 00:25:39 codeman kernel: EXT3-fs error (device ide0(3,9)) in 
ext3_truncate: Journal has aborted
Dec  3 00:25:39 codeman kernel: ext3_reserve_inode_write: aborting 
transaction: Journal has aborted in __ext3_journal_get_write_acce
ss<2>EXT3-fs error (device ide0(3,9)) in ext3_reserve_inode_write: Journal has 
aborted
Dec  3 00:25:39 codeman kernel: EXT3-fs error (device ide0(3,9)) in 
ext3_orphan_del: Journal has aborted
Dec  3 00:25:39 codeman kernel: ext3_reserve_inode_write: aborting 
transaction: Journal has aborted in __ext3_journal_get_write_acce
ss<2>EXT3-fs error (device ide0(3,9)) in ext3_reserve_inode_write: Journal has 
aborted
Dec  3 00:25:39 codeman kernel: EXT3-fs error (device ide0(3,9)) in 
ext3_delete_inode: Journal has aborted
Dec  3 00:25:39 codeman kernel: ext3_abort called.
Dec  3 00:25:39 codeman kernel: EXT3-fs abort (device ide0(3,9)): 
ext3_journal_start: Detected aborted journal
Dec  3 00:25:39 codeman kernel: Remounting filesystem read-only
Dec  3 00:25:39 codeman kernel: EXT3-fs error (device ide0(3,9)) in 
start_transaction: Journal has aborted

BTW: UP, non-SMP.

ciao, Marc

^ permalink raw reply	[flat|nested] 39+ messages in thread

end of thread, other threads:[~2002-12-05 23:06 UTC | newest]

Thread overview: 39+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2002-11-29 11:54 Exaggerated swap usage Javier Marcet
2002-11-29 12:20 ` Christer Nilsson
2002-11-29 16:31 ` Rik van Riel
2002-11-30  1:38   ` Javier Marcet
2002-11-30  1:55     ` Rik van Riel
2002-11-30  2:47       ` Zwane Mwaikambo
2002-11-30  5:17       ` Javier Marcet
2002-11-30 14:02       ` Exaggerated swap usage && -aa lockup Javier Marcet
2002-11-30  2:42     ` Exaggerated swap usage Zwane Mwaikambo
2002-11-30  3:02       ` Andrew Morton
2002-11-30  4:12         ` Zwane Mwaikambo
2002-11-30  6:48           ` khromy
2002-11-30  6:49             ` Javier Marcet
2002-11-30  7:08               ` Dmitri
2002-11-30 14:05                 ` Javier Marcet
2002-11-30 18:23               ` khromy
2002-11-30 18:43                 ` Andrea Arcangeli
2002-12-01  7:39                   ` Javier Marcet
2002-12-01  7:53                   ` Javier Marcet
2002-12-01 10:34                     ` Andrea Arcangeli
2002-12-01  7:59                   ` Javier Marcet
2002-12-01 10:36                     ` Andrea Arcangeli
2002-12-01 14:37                       ` Nuno Monteiro
2002-12-02  0:21                         ` Andrea Arcangeli
2002-12-02  1:01                           ` Nuno Monteiro
2002-12-02  4:55                           ` Javier Marcet
2002-12-02 21:24                           ` Andrew Clayton
2002-11-30 14:05   ` Steffen Moser
2002-11-30 18:22     ` Rik van Riel
2002-12-01  7:57       ` Javier Marcet
2002-12-01 19:27         ` Rik van Riel
  -- strict thread matches above, loose matches on Subject: below --
2002-11-29 15:28 Randal, Phil
2002-11-29 16:28 ` Rik van Riel
2002-12-02 23:59 Marc-Christian Petersen
2002-12-03  0:59 ` Andrea Arcangeli
2002-12-03 10:13   ` Marc-Christian Petersen
2002-12-03 13:59     ` Andrea Arcangeli
2002-12-03 18:43       ` Marc-Christian Petersen
2002-12-05 23:14         ` Marc-Christian Petersen

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox