From: Michal Hocko <mhocko@suse.com>
To: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>,
Linux MM <linux-mm@kvack.org>,
Andrew Morton <akpm@linux-foundation.org>,
Roman Gushchin <guro@fb.com>, LKML <linux-kernel@vger.kernel.org>,
Greg Thelen <gthelen@google.com>
Subject: Re: Machine lockups on extreme memory pressure
Date: Tue, 22 Sep 2020 17:16:54 +0200 [thread overview]
Message-ID: <20200922151654.GA12990@dhcp22.suse.cz> (raw)
In-Reply-To: <CALvZod6=VwQduoG3GiW-=csAQja4vCsXAhKH_tSuA4JYx0dEiA@mail.gmail.com>
On Tue 22-09-20 06:37:02, Shakeel Butt wrote:
[...]
> > I would recommend to focus on tracking down the who is blocking the
> > further progress.
>
> I was able to find the CPU next in line for the list_lock from the
> dump. I don't think anyone is blocking the progress as such but more
> like the spinlock in the irq context is starving the spinlock in the
> process context. This is a high traffic machine and there are tens of
> thousands of potential network ACKs on the queue.
So there is a forward progress but it is too slow to have any reasonable
progress in userspace?
> I talked about this problem with Johannes at LPC 2019 and I think we
> talked about two potential solutions. First was to somehow give memory
> reserves to oomd and second was in-kernel PSI based oom-killer. I am
> not sure the first one will work in this situation but the second one
> might help.
Why does your oomd depend on memory allocation?
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2020-09-22 15:16 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-21 18:35 Shakeel Butt
2020-09-22 11:12 ` Michal Hocko
2020-09-22 13:37 ` Shakeel Butt
2020-09-22 15:16 ` Michal Hocko [this message]
2020-09-22 16:29 ` Shakeel Butt
2020-09-22 16:34 ` Michal Hocko
2020-09-22 16:51 ` Shakeel Butt
2020-09-22 17:01 ` Michal Hocko
2020-10-30 17:01 ` Shakeel Butt
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