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Comments: In-reply-to Danny Braniss <danny@cs.huji.ac.il>
	message dated "Sat, 27 Sep 2008 14:32:55 +0300."
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Date: Mon, 29 Sep 2008 10:56:32 +0300
From: Danny Braniss <danny@cs.huji.ac.il>
Message-ID: <E1KkDcO-000971-Co@cs1.cs.huji.ac.il>
Cc: freebsd-hackers@freebsd.org, Jeremy Chadwick <koitsu@FreeBSD.org>,
	freebsd-stable@freebsd.org
Subject: Re: bad NFS/UDP performance 
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> > On Fri, 26 Sep 2008, Danny Braniss wrote:
> > 
> > > after more testing, it seems it's related to changes made between Aug 4 and 
> > > Aug 29 ie, a kernel built on Aug 4 works fine, Aug 29 is slow. I'l now try 
> > > and close the gap.
> > 
> > I think this is the best way forward -- skimming August changes, there are a 
> > number of candidate commits, including retuning of UDP hashes by mav, my 
> > rwlock changes, changes to mbuf chain handling, etc.
> 
> it more difficult than I expected.
> for one, the kernel date was missleading, the actual source update is the key, so
> the window of changes is now 28/July to 19/August. I have the diffs, but nothing
> yet seems relevant.
> 
> on the other hand, I tried NFS/TCP, and there things seem ok, ie the 'good' and the 'bad'
> give the same throughput, which seem to point to UDP changes ...
> 
> danny

Grr, there goes binary search theory out of the window,
So far I have managed to pinpoint the day that the changes affect the 
throughput:
	18/08/08 00:00:00 	19/08/08 00:00:00
(I assume cvs's date is GMT).
now would be a good time for some help, specially how to undo changes, my
knowledge of csup/cvs are close to zero.

danny