lkml.org 
[lkml]   [2012]   [Jan]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Kswapd in 3.2.0-rc5 is a CPU hog
On Tue, 27 Dec 2011 13:56:58 +0900
KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> wrote:

> Hmm, if I understand correctly,
>
> - dd's speed down is caused by kswapd's cpu consumption.
> - kswapd's cpu consumption is enlarged by shrink_slab() (by perf)
> - kswapd can't stop because NORMAL zone is small.
> - memory reclaim speed is enough because dd can't get enough cpu.
>
> I wonder reducing to call shrink_slab() may be a help but I'm not sure
> where lock conention comes from...

Nikolay, it sounds as if this problem has only recently started
happening? Was 3.1 OK?

If so, we should work out what we did post-3.1 to cause this.


\
 
 \ /
  Last update: 2012-01-10 23:35    [W:0.078 / U:0.360 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site