Re: running of out memory => kernel crash

From: David Rientjes
Date: Thu Aug 11 2011 - 03:13:20 EST


On Thu, 11 Aug 2011, Mahmood Naderan wrote:

> >The default behavior is to kill all eligible and unkillable threads until
> >there are none left to sacrifice (i.e. all kthreads and OOM_DISABLE).
>  
> In a simple test with virtualbox, I reduced the amount of ram to 300MB.
> Then I ran "swapoff -a" and opened some applications. I noticed that the free
> spaces is kept around 2-3MB and "kswapd" is running. Also I saw that disk
> activity was very high.
> That mean although "swap" partition is turned off, "kswapd" was trying to do
> something. I wonder how that behavior can be explained?
>

Despite it's name, kswapd is still active, it's trying to reclaim memory
to prevent having to kill a process as the last resort.

If /proc/sys/vm/panic_on_oom is not set, as previously mentioned, then
we'll need the kernel log to diagnose this further.