From: Lee Revell <rlrevell@joe-job.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>,
Andrew Morton <akpm@osdl.org>,
linux-kernel@vger.kernel.org
Subject: Re: NFS client latencies
Date: Thu, 31 Mar 2005 21:28:36 -0500 [thread overview]
Message-ID: <1112322516.2509.28.camel@mindpipe> (raw)
In-Reply-To: <20050331145015.GA4830@elte.hu>
On Thu, 2005-03-31 at 16:50 +0200, Ingo Molnar wrote:
> * Ingo Molnar <mingo@elte.hu> wrote:
>
> > > So the overhead you are currently seeing should just be that of
> > > iterating through the list, locking said requests and adding them to
> > > our private list.
> >
> > ah - cool! This was a 100 MB writeout so having 3.7 msecs to process
> > 20K+ pages is not unreasonable. To break the latency, can i just do a
> > simple lock-break, via the patch below?
>
> with this patch the worst-case latency during NFS writeout is down to 40
> usecs (!).
>
> Lee: i've uploaded the -42-05 release with this patch included - could
> you test it on your (no doubt more complex than mine) NFS setup?
This fixes all the NFS related latency problems I was seeing. Now the
longest latency from an NFS kernel compile with "make -j64" is 391 usecs
in get_swap_page.
Lee
next prev parent reply other threads:[~2005-04-01 2:28 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-03-29 23:04 NFS client latencies Lee Revell
2005-03-29 23:18 ` Trond Myklebust
2005-03-29 23:32 ` Lee Revell
2005-03-29 23:34 ` Trond Myklebust
2005-03-29 23:37 ` Lee Revell
2005-03-30 8:02 ` Ingo Molnar
2005-03-30 14:11 ` Trond Myklebust
2005-03-30 14:20 ` Ingo Molnar
2005-03-30 19:53 ` Andrew Morton
2005-03-30 14:26 ` Lee Revell
2005-03-30 14:50 ` Trond Myklebust
2005-03-30 19:50 ` Lee Revell
2005-03-30 19:56 ` Andrew Morton
2005-03-30 21:14 ` Trond Myklebust
2005-03-31 2:26 ` Lee Revell
2005-03-31 2:39 ` Andrew Morton
2005-03-31 2:47 ` Lee Revell
2005-03-31 3:48 ` Trond Myklebust
2005-03-31 6:59 ` Ingo Molnar
2005-03-31 7:15 ` Ingo Molnar
2005-03-31 7:18 ` Andrew Morton
2005-03-31 7:30 ` Ingo Molnar
2005-03-31 11:58 ` Trond Myklebust
2005-03-31 12:34 ` Trond Myklebust
2005-03-31 13:58 ` Ingo Molnar
2005-03-31 14:32 ` Trond Myklebust
2005-03-31 14:39 ` Ingo Molnar
2005-03-31 14:50 ` Ingo Molnar
2005-04-01 2:28 ` Lee Revell [this message]
2005-04-01 4:30 ` Ingo Molnar
2005-04-01 16:16 ` Orion Poplawski
2005-04-01 16:33 ` Trond Myklebust
2005-04-01 21:18 ` Lee Revell
2005-03-31 14:54 ` Ingo Molnar
2005-03-31 15:00 ` Trond Myklebust
2005-03-31 14:54 ` Trond Myklebust
2005-03-31 14:58 ` Ingo Molnar
2005-03-31 15:06 ` Trond Myklebust
2005-03-31 15:10 ` Ingo Molnar
2005-03-31 16:00 ` Trond Myklebust
2005-03-31 15:10 ` Ingo Molnar
2005-03-31 7:03 ` Ingo Molnar
2005-03-31 7:39 ` Ingo Molnar
2005-03-31 7:48 ` Ingo Molnar
2005-03-31 7:58 ` Ingo Molnar
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