On Tue, 08 Mar 2011 22:02:27 +0300 "avagin@xxxxxxxxx" <avagin@xxxxxxxxx> wrote: > On 03/08/2011 06:06 AM, KOSAKI Motohiro wrote: > >>>> Hmm.. Although it solves the problem, I think it's not a good idea that > >>>> depends on false alram and give up the retry. > >>> > >>> Any alternative proposals? We should get the livelock fixed if possible.. > >> > >> I agree with Minchan and can't think this is a real fix.... > >> Andrey, I'm now trying your fix and it seems your fix for oom-killer, > >> 'skip-zombie-process' works enough good for my environ. > >> > >> What is your enviroment ? number of cpus ? architecture ? size of memory ? > > > > me too. 'skip-zombie-process V1' work fine. and I didn't seen this patch > > improve oom situation. > > > > And, The test program is purely fork bomb. Our oom-killer is not silver > > bullet for fork bomb from very long time ago. That said, oom-killer send > > SIGKILL and start to kill the victim process. But, it doesn't prevent > > to be created new memory hogging tasks. Therefore we have no gurantee > > to win process exiting and creating race. > > I think a live-lock is a bug, even if it's provoked by fork bomds. > I tried to write fork-bomb-detector in oom-kill layer but I think it should be co-operative with do_fork(), now. IOW, some fork() should return -ENOMEM under OOM condition. I'd like to try some but if you have some idea, please do. > And now I want say some words about zone->all_unreclaimable. I think > this flag is "conservative". It is set when situation is bad and it's > unset when situation get better. If we have a small number of > reclaimable pages, the situation is still bad. What do you mean, when > say that kernel is alive? If we have one reclaimable page, is the kernel > alive? Yes, it can work, it will generate many page faults and do > something, but anyone say that it is more dead than alive. > > Try to look at it from my point of view. The patch will be correct and > the kernel will be more alive. > > Excuse me, If I'm mistaken... > Mayne something more casual interface than oom-kill should be provided. I wonder I can add memory-reclaim-priority to memory cgroup and allow control of page fault latency for applicaton... Maybe "soft_limit" for memcg, it's implemented now, works to some extent. Thanks, -Kame -- 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=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>