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Comments: In-reply-to Gavin Atkinson <gavin@FreeBSD.org>
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Date: Fri, 26 Sep 2008 16:41:22 +0300
From: Danny Braniss <danny@cs.huji.ac.il>
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Cc: freebsd-hackers@FreeBSD.org, freebsd-stable@FreeBSD.org
Subject: Re: bad NFS/UDP performance 
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> On Fri, 2008-09-26 at 10:04 +0300, Danny Braniss wrote:
> > Hi,
> > 	There seems to be some serious degradation in performance.
> > Under 7.0 I get about 90 MB/s (on write), while, on the same machine
> > under 7.1 it drops to 20!
> > Any ideas?
> 
> The scheduler has been changed to ULE, and NFS has historically been
> very sensitive to changes like that.  You could try switching back to
> the 4BSD scheduler and seeing if that makes a difference.  If it does,
> toggling PREEMPTION would also be interesting to see the results of.
> 
> Gavin

I'm testing 7.0-stable vs 7.1-prerelease, and both have ULE.
BTW, the nfs client hosts I'm testing are idle.

danny