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From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: Ion Badulescu <ionut@badula.org>, linux-kernel@vger.kernel.org
Subject: Re: rcu stalls and soft lockups with recent kernels
Date: Fri, 18 Mar 2016 03:28:57 +0100	[thread overview]
Message-ID: <1458268137.3859.5.camel@gmail.com> (raw)
In-Reply-To: <56E9868E.4000006@badula.org>

On Wed, 2016-03-16 at 12:15 -0400, Ion Badulescu wrote:
> Just following up to my own email:
> 
> It turns out that we can eliminate the RCU stalls by changing from 
> CONFIG_RCU_NOCB_CPU_ALL to CONFIG_RCU_NOCB_CPU_NONE. Letting each cpu 
> handle its own RCU callbacks completely fixes the problems for us.
> 
> Now, CONFIG_NO_HZ_FULL and CONFIG_RCU_NOCB_CPU_ALL is the default config 
> for fedora and rhel7. Ho-humm...

All RCU offloaded to CPU0 of a big box seems like a very bad idea.

	-Mike

  reply	other threads:[~2016-03-18  2:29 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <56B39F0C.7070406@badula.org>
2016-02-04 19:12 ` rcu stalls and soft lockups with recent kernels Ion Badulescu
2016-03-16 16:15   ` Ion Badulescu
2016-03-18  2:28     ` Mike Galbraith [this message]
2016-03-22 20:22       ` Ion Badulescu
2016-03-23  4:50         ` Mike Galbraith
2016-03-23 15:36           ` Paul E. McKenney

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