From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
To: Benjamin Segall <bsegall-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Cc: Zhang Qiao <zhangqiao22-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>,
mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org,
peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org,
Juri Lelli <juri.lelli-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
Vincent Guittot
<vincent.guittot-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>,
lizefan.x-EC8Uxl6Npydl57MIdRCFDg@public.gmane.org,
hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org,
cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
lkml <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
vschneid-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org,
dietmar.eggemann-5wv7dgnIgG8@public.gmane.org,
bristot-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org,
Steven Rostedt <rostedt-nx8X9YLhiw1AfugRpC6u6w@public.gmane.org>,
mgorman-l3A5Bk7waGM@public.gmane.org
Subject: Re: [Question] The system may be stuck if there is a cpu cgroup cpu.cfs_quato_us is very low
Date: Sat, 2 Jul 2022 05:15:43 +0900 [thread overview]
Message-ID: <Yr9V755mL6jr20c2@mtj.duckdns.org> (raw)
In-Reply-To: <xm26czeoioju.fsf-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
On Fri, Jul 01, 2022 at 01:08:21PM -0700, Benjamin Segall wrote:
> Yes, fixing (kernel) priority inversion due to CFS_BANDWIDTH requires a
> serious reworking of how it works, because it would need to dequeue
> tasks individually rather than doing the entire cfs_rq at a time (and
> would require some effort to avoid pinging every throttling task to get
> it into the kernel).
Right, I don't have a good idea on evolving the current implementation
into something correct. As you pointed out, we need to account along
the sched_group tree but conditionally enforce on each thread.
Thanks.
--
tejun
next prev parent reply other threads:[~2022-07-01 20:15 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-27 6:50 [Question] The system may be stuck if there is a cpu cgroup cpu.cfs_quato_us is very low Zhang Qiao
[not found] ` <5987be34-b527-4ff5-a17d-5f6f0dc94d6d-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2022-06-27 8:32 ` Tejun Heo
[not found] ` <YrlrBmF3oOfS3+fq-qYNAdHglDFBN0TnZuCh8vA@public.gmane.org>
2022-07-01 7:34 ` Zhang Qiao
[not found] ` <f0f55f89-14db-de29-c182-32539f8d4e4d-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2022-07-01 20:08 ` Benjamin Segall
[not found] ` <xm26czeoioju.fsf-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2022-07-01 20:15 ` Tejun Heo [this message]
[not found] ` <Yr9V755mL6jr20c2-qYNAdHglDFBN0TnZuCh8vA@public.gmane.org>
2022-07-07 6:59 ` Zhang Qiao
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