From: Peter Zijlstra <peterz@infradead.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>,
linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
Frederic Weisbecker <fweisbec@gmail.com>
Subject: Re: 4.2.2: NR_CPUS effectively being 1 bug
Date: Sat, 3 Oct 2015 08:53:20 +0200 [thread overview]
Message-ID: <20151003065320.GE3816@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <20151002140033.ef62cd83936263311eb210d8@linux-foundation.org>
On Fri, Oct 02, 2015 at 02:00:33PM -0700, Andrew Morton wrote:
> On Fri, 2 Oct 2015 23:46:59 +0300 Alexey Dobriyan <adobriyan@gmail.com> wrote:
>
> > FYI, I've upgraded from 4.1.7 to 4.2.1 (and retested with 4.2.2) and
> > everything is scheduled on 1 CPU out of 4 (i5 760).
> >
> > $ sudo cat /proc/1/status | grep cpu -i
> > Cpus_allowed: 1
> > Cpus_allowed_list: 0
> >
> > Every process inherits this tiny cpumask.
>
> Sell the other CPUs on ebay?
>
> I haven't seen such a report before - maybe it rings a bell with Peter
> & Ingo?
I think this is related to some NO_HZ_FULL quackery. People seem to have
enabled stuff they've really no sane reason for.
next prev parent reply other threads:[~2015-10-03 6:59 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-02 20:46 4.2.2: NR_CPUS effectively being 1 bug Alexey Dobriyan
2015-10-02 21:00 ` Andrew Morton
2015-10-03 6:53 ` Peter Zijlstra [this message]
2015-10-03 7:38 ` Ingo Molnar
2015-10-03 8:15 ` Mike Galbraith
2015-10-03 8:18 ` Ingo Molnar
2015-10-03 8:24 ` Mike Galbraith
2015-10-03 8:52 ` Ingo Molnar
2015-10-03 12:04 ` Mike Galbraith
2015-10-03 12:31 ` Frederic Weisbecker
2015-10-03 12:49 ` Mike Galbraith
2015-10-03 12:14 ` Alexey Dobriyan
2015-10-03 12:19 ` Mike Galbraith
2015-10-03 6:50 ` Afzal Mohammed
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