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Subject: Re: oom_killer crash linux system
From: "Figo.zhang" <zhangtianfei@leadcoretech.com>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
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Date: Wed, 20 Oct 2010 09:36:47 +0800
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>
> >
> > echo 5 > /proc/sys/vm/dirty_ratio
>
> reduce the dirty_ratio, i can use memory up to 1.75GB, and then it
will
> call oom-killer.
>So it helps.  Are there intensive IO after reducing dirty_ratio?

> > - enable vmscan trace
> >
> > mount -t debugfs none /sys/kernel/debug
> > echo 1 > /sys/kernel/debug/tracing/events/vmscan/enable
> > <eat memory and wait for crash>
> > cat /sys/kernel/debug/tracing/trace > trace.log
> would you like to help to see the trace.log , i add attached file.
> There are many vmscan writes showing up in the trace.

yes, the DiskIO is be not aggressive when i reduce the dirty_ratio, but
when i use memory up to 1.75GB (total 2GB), the system suddenly crashed.
when i reboot and want to see the /var/log/message, it is without useful
information.

so it is other useful debug approach to find the issue?