Messages in this thread | | | Date | Mon, 31 May 2010 15:09:41 +0900 | Subject | Re: [RFC] oom-kill: give the dying task a higher priority | From | Minchan Kim <> |
| |
On Mon, May 31, 2010 at 2:54 PM, KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> wrote: > On Mon, 31 May 2010 14:46:05 +0900 > Minchan Kim <minchan.kim@gmail.com> wrote: > >> On Mon, May 31, 2010 at 2:04 PM, KAMEZAWA Hiroyuki >> <kamezawa.hiroyu@jp.fujitsu.com> wrote: >> > On Mon, 31 May 2010 14:01:03 +0900 >> > Minchan Kim <minchan.kim@gmail.com> wrote: >> > >> >> Hi, Kame. >> >> >> >> On Mon, May 31, 2010 at 9:21 AM, KAMEZAWA Hiroyuki >> >> <kamezawa.hiroyu@jp.fujitsu.com> wrote: >> >> > On Fri, 28 May 2010 13:48:26 -0300 >> >> > "Luis Claudio R. Goncalves" <lclaudio@uudg.org> wrote: >> >> >> >> >> >> oom-killer: give the dying task rt priority (v3) >> >> >> >> >> >> Give the dying task RT priority so that it can be scheduled quickly and die, >> >> >> freeing needed memory. >> >> >> >> >> >> Signed-off-by: Luis Claudio R. Gonçalves <lgoncalv@redhat.com> >> >> >> >> >> >> diff --git a/mm/oom_kill.c b/mm/oom_kill.c >> >> >> index 84bbba2..2b0204f 100644 >> >> >> --- a/mm/oom_kill.c >> >> >> +++ b/mm/oom_kill.c >> >> >> @@ -266,6 +266,8 @@ static struct task_struct *select_bad_process(unsigned long *ppoints) >> >> >> */ >> >> >> static void __oom_kill_task(struct task_struct *p, int verbose) >> >> >> { >> >> >> + struct sched_param param; >> >> >> + >> >> >> if (is_global_init(p)) { >> >> >> WARN_ON(1); >> >> >> printk(KERN_WARNING "tried to kill init!\n"); >> >> >> @@ -288,6 +290,8 @@ static void __oom_kill_task(struct task_struct *p, int verbose) >> >> >> * exit() and clear out its resources quickly... >> >> >> */ >> >> >> p->time_slice = HZ; >> >> >> + param.sched_priority = MAX_RT_PRIO-10; >> >> >> + sched_setscheduler(p, SCHED_FIFO, ¶m); >> >> >> set_tsk_thread_flag(p, TIF_MEMDIE); >> >> >> >> >> > >> >> > BTW, how about the other threads which share mm_struct ? >> >> >> >> Could you elaborate your intention? :) >> >> >> > >> > IIUC, the purpose of rising priority is to accerate dying thread to exit() >> > for freeing memory AFAP. But to free memory, exit, all threads which share >> > mm_struct should exit, too. I'm sorry if I miss something. >> >> How do we kill only some thread and what's the benefit of it? >> I think when if some thread receives KILL signal, the process include >> the thread will be killed. >> > yes, so, if you want a _process_ die quickly, you have to acceralte the whole > threads on a process. Acceralating a thread in a process is not big help.
Yes.
I see the code. oom_kill_process is called by
1. mem_cgroup_out_of_memory 2. __out_of_memory 3. out_of_memory
(1,2) calls select_bad_process which select victim task in processes by do_each_process. But 3 isn't In case of CONSTRAINT_MEMORY_POLICY, it kills current. In only the case, couldn't we pass task of process, not one of thread?
> > Thanks, > -Kame > >
-- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |