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From: Jeff Layton <jlayton@kernel.org>
To: Stefan Kooman <stefan@bit.nl>,
	Ceph Development <ceph-devel@vger.kernel.org>
Subject: Re: Investigate busy ceph-msgr worker thread
Date: Thu, 03 Dec 2020 11:46:02 -0500	[thread overview]
Message-ID: <ac5253d71ea50c8f5b4e50a07a1a0180abd58562.camel@kernel.org> (raw)
In-Reply-To: <9afdb763-4cf6-3477-bd32-762840c0c0a5@bit.nl>

On Thu, 2020-12-03 at 12:01 +0100, Stefan Kooman wrote:
> Hi,
> 
> We have a cephfs linux kernel (5.4.0-53-generic) workload (rsync) that 
> seems to be limited by a single ceph-msgr thread (doing close to 100% 
> cpu). We would like to investigate what this thread is so busy with. 
> What would be the easiest way to do this? On a related note: what would 
> be the best way to scale cephfs client performance for a single process 
> (if at all possible)?
> 
> Thanks for any pointers.
> 

Usually kernel profiling (a'la perf) is the way to go about this. You
may want to consider trying more recent kernels and see if they fare any
better. With a new enough MDS and kernel, you can try enabling async
creates as well, and see whether that helps performance any.

As far as optimizing for a single process, there's not a lot you can do,
really.
-- 
Jeff Layton <jlayton@kernel.org>


  reply	other threads:[~2020-12-03 16:47 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-03 11:01 Investigate busy ceph-msgr worker thread Stefan Kooman
2020-12-03 16:46 ` Jeff Layton [this message]
2020-12-04 19:49   ` Stefan Kooman
2020-12-04 21:13     ` Jeff Layton

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