CAM disk I/O starvation

Gary Jennejohn gljennjohn at googlemail.com
Wed Apr 11 17:21:59 UTC 2012


On Tue, 3 Apr 2012 14:27:43 -0700
Jerry Toung <jrytoung at gmail.com> wrote:

> On 4/3/12, Gary Jennejohn <gljennjohn at 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


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