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Date: Wed, 11 Apr 2012 19:21:53 +0200
From: Gary Jennejohn <gljennjohn@googlemail.com>
To: Jerry Toung <jrytoung@gmail.com>
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Cc: freebsd-hackers <freebsd-hackers@freebsd.org>
Subject: Re: CAM disk I/O starvation
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On Tue, 3 Apr 2012 14:27:43 -0700
Jerry Toung <jrytoung@gmail.com> wrote:

> On 4/3/12, Gary Jennejohn <gljennjohn@googlemail.com> wrote:
> 
> > It would be interesting to see your patch.  I always run HEAD but maybe
> > I could use it as a base for my own mods/tests.
> >
> 
> Here is the patch
> 

[patch removed]

Just for the archive my bad disk performance seems to have been fixed in
HEAD by svn commit r234074.  Seems that all interrupts were being handled
by a single CPU/core (I have 6), which resulted in abysmal interrupt
handling when mutltiple disks were busy.

Since this commit my disk preformance is back to normal and long lags
are a thing of the past.

-- 
Gary Jennejohn