oom-kill: add lowmem usage aware oom kill handling
in [Kernel]
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From: Minchan Kim on 22 Jan 2010 09:10 On Fri, 2010-01-22 at 15:23 +0900, KAMEZAWA Hiroyuki wrote: > updated. thank you for review. > > The patch is onto mmotm-Jan15 (depends on mm-count-lowmem-rss.patch) > Tested on x86-64/SMP + debug module(to allocated lowmem), works well. > > == > From: KAMEZAWA Hiroyuki <kamezawa.hiroyu(a)jp.fujitsu.com> > > Default oom-killer uses badness calculation based on process's vm_size > and some amounts of heuristics. Some users see proc->oom_score and > proc->oom_adj to control oom-killed tendency under their server. > > Now, we know oom-killer don't work ideally in some situaion, in PCs. Some > enhancements are demanded. But such enhancements for oom-killer makes > incomaptibility to oom-controls in enterprise world. So, this patch > adds sysctl for extensions for oom-killer. Main purpose is for > making a chance for wider test for new scheme. > > One cause of OOM-Killer is memory shortage in lower zones. > (If memory is enough, lowmem_reserve_ratio works well. but..) > I saw lowmem-oom frequently on x86-32 and sometimes on ia64 in > my cusotmer support jobs. If we just see process's vm_size at oom, > we can never kill a process which has lowmem. > At last, there will be an oom-serial-killer. > > Now, we have per-mm lowmem usage counter. We can make use of it > to select a good victim. > > This patch does > - add sysctl for new bahavior. > - add CONSTRAINT_LOWMEM to oom's constraint type. > - pass constraint to __badness() > - change calculation based on constraint. If CONSTRAINT_LOWMEM, > use low_rss instead of vmsize. > > Changelog 2010/01/22: > - added sysctl > - fixed !CONFIG_MMU > - fixed fs/proc/base.c breakacge. > > Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu(a)jp.fujitsu.com> > --- > Documentation/sysctl/vm.txt | 16 ++++++++ > fs/proc/base.c | 5 +- > include/linux/oom.h | 1 > kernel/sysctl.c | 10 ++++- > mm/oom_kill.c | 87 ++++++++++++++++++++++++++++++++------------ > 5 files changed, 94 insertions(+), 25 deletions(-) > > Index: mmotm-2.6.33-Jan15/include/linux/oom.h > =================================================================== > --- mmotm-2.6.33-Jan15.orig/include/linux/oom.h > +++ mmotm-2.6.33-Jan15/include/linux/oom.h > @@ -20,6 +20,7 @@ struct notifier_block; > */ > enum oom_constraint { > CONSTRAINT_NONE, > + CONSTRAINT_LOWMEM, > CONSTRAINT_CPUSET, > CONSTRAINT_MEMORY_POLICY, > }; <snip> > @@ -475,7 +511,7 @@ void mem_cgroup_out_of_memory(struct mem > > read_lock(&tasklist_lock); > retry: > - p = select_bad_process(&points, mem); > + p = select_bad_process(&points, mem, CONSTRAINT_NONE); Why do you fix this with only CONSTRAINT_NONE? I think we can know CONSTRAINT_LOWMEM with gfp_mask in here. Any problem? Otherwise, Looks good to me. :) Reviewed-by: Minchan Kim <minchan.kim(a)gmail.com> -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: KAMEZAWA Hiroyuki on 22 Jan 2010 10:20 Minchan Kim wrote: > On Fri, 2010-01-22 at 15:23 +0900, KAMEZAWA Hiroyuki wrote: >> updated. thank you for review. >> CONSTRAINT_MEMORY_POLICY, >> }; > > <snip> >> @@ -475,7 +511,7 @@ void mem_cgroup_out_of_memory(struct mem >> >> read_lock(&tasklist_lock); >> retry: >> - p = select_bad_process(&points, mem); >> + p = select_bad_process(&points, mem, CONSTRAINT_NONE); > > Why do you fix this with only CONSTRAINT_NONE? > I think we can know CONSTRAINT_LOWMEM with gfp_mask in here. > memcg is just for accounting anon/file pages. Then, it's never cause lowmem oom problem (any memory is ok for memcg). > Any problem? > > Otherwise, Looks good to me. :) > > Reviewed-by: Minchan Kim <minchan.kim(a)gmail.com> > Thank you. -Kame > -- > Kind regards, > Minchan Kim > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Minchan Kim on 22 Jan 2010 10:50 2010/1/23 KAMEZAWA Hiroyuki <kamezawa.hiroyu(a)jp.fujitsu.com>: >> <snip> >>> @@ -475,7 +511,7 @@ void mem_cgroup_out_of_memory(struct mem >>> >>> read_lock(&tasklist_lock); >>> retry: >>> - p = select_bad_process(&points, mem); >>> + p = select_bad_process(&points, mem, CONSTRAINT_NONE); >> >> Why do you fix this with only CONSTRAINT_NONE? >> I think we can know CONSTRAINT_LOWMEM with gfp_mask in here. >> > memcg is just for accounting anon/file pages. Then, it's never > cause lowmem oom problem (any memory is ok for memcg). Okay. Thanks for the explanation. -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Andrew Morton on 26 Jan 2010 18:20 On Mon, 25 Jan 2010 15:15:03 +0900 KAMEZAWA Hiroyuki <kamezawa.hiroyu(a)jp.fujitsu.com> wrote: > -unsigned long badness(struct task_struct *p, unsigned long uptime) > +unsigned long badness(struct task_struct *p, unsigned long uptime, > + int constraint) And badness() should be renamed to something better (eg, oom_badness), and the declaration should be placed in a mm-specific header file. Yes, the code was already like that. But please don't leave crappiness in place when you come across it - take the opportunity to fix it up. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: KAMEZAWA Hiroyuki on 26 Jan 2010 18:50
On Tue, 26 Jan 2010 15:16:06 -0800 Andrew Morton <akpm(a)linux-foundation.org> wrote: > On Mon, 25 Jan 2010 15:15:03 +0900 > KAMEZAWA Hiroyuki <kamezawa.hiroyu(a)jp.fujitsu.com> wrote: > > > -unsigned long badness(struct task_struct *p, unsigned long uptime) > > +unsigned long badness(struct task_struct *p, unsigned long uptime, > > + int constraint) > > And badness() should be renamed to something better (eg, oom_badness), and > the declaration should be placed in a mm-specific header file. > > Yes, the code was already like that. But please don't leave crappiness in > place when you come across it - take the opportunity to fix it up. > Sure. I'll write v4. -Kame -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |