Re: Kernel falls apart under light memory pressure (i.e. linking vmlinux)

[Andrew Lutomirski]

[cc linux-mm]

On Thu, May 12, 2011 at 7:54 AM, Andrew Lutomirski <luto@xxxxxxx> wrote:
> On Thu, May 12, 2011 at 1:46 AM, Andi Kleen <andi@xxxxxxxxxxxxxx> wrote:
>>> Here's a nice picture of alt-sysrq-m with lots of memory free but the
>>> system mostly hung.  I can still switch VTs.
>>
>> Would rather need backtraces. Try setting up netconsole or crashdump
>> first.
>
> Here are some logs for two different failure mores.
>
> incorrect_oom_kill.txt is an OOM kill when there was lots of available
> swap to use.  AFAICT the kernel should not have OOM killed at all.
>
> stuck_xyz is when the system is wedged with plenty (~300MB) free
> memory but no swap.  The sysrq files are self-explanatory.
> stuck-sysrq-f.txt is after the others so that it won't have corrupted
> the output.  After taking all that data, I waited awhile and started
> getting soft lockup messges.
>
> I'm having trouble reproducing the "stuck" failure mode on my
> lockdep-enabled kernel right now (the OOM kill is easy), so no lock
> state trace.  But I got one yesterday and IIRC it showed a few tty
> locks and either kworker or kcryptd holding (kqueue) and
> ((&io->work)).
>
> I compressed the larger files.
>
> --Andy
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/