Re: [PATCH 3/5] oom: create oom autogroup

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


On Tue, Mar 22, 2011 at 8:08 PM, KOSAKI Motohiro
<kosaki.motohiro@xxxxxxxxxxxxxx> wrote:
> When plenty processes (eg fork bomb) are running, the TIF_MEMDIE task
> never exit, at least, human feel it's never. therefore kernel become
> hang-up.
>
> "perf sched" tell us a hint.
>
> Â------------------------------------------------------------------------------
> ÂTask         Â|  Runtime ms Â| Average delay ms | Maximum delay ms |
> Â------------------------------------------------------------------------------
> Âpython:1754 Â Â Â Â Â | Â Â Â0.197 ms | avg: 1731.727 ms | max: 3433.805 ms |
> Âpython:1843 Â Â Â Â Â | Â Â Â0.489 ms | avg: 1707.433 ms | max: 3622.955 ms |
> Âpython:1715 Â Â Â Â Â | Â Â Â0.220 ms | avg: 1707.125 ms | max: 3623.246 ms |
> Âpython:1818 Â Â Â Â Â | Â Â Â2.127 ms | avg: 1527.331 ms | max: 3622.553 ms |
> Â...
> Â...
>
> Processes flood makes crazy scheduler delay. and then the victim process
> can't run enough. Grr. Should we do?
>
> Fortunately, we already have anti process flood framework, autogroup!
> This patch reuse this framework and avoid kernel live lock.

That's cool idea but I have a concern.

You remove boosting priority in [2/5] and move victim tasks into autogroup.
If I understand autogroup right, victim process and threads in the
process take less schedule chance than now.

Could it make unnecessary killing of other tasks?
I am not sure. Just out of curiosity.

Thanks for nice work, Kosaki.
-- 
Kind regards,
Minchan Kim

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxxx  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href


[Site Home]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Security]     [Bugtraq]     [Linux]     [Linux OMAP]     [Linux MIPS]     [ECOS]     [Tools]     [DDR & Rambus]     [Asterisk Internet PBX]     [Linux API]     [Monitors]

Add to Google Google PageRank Checking tool