3w-9xxx module version in FC4

[David Kewley]

Jesse Keating wrote on Friday 29 April 2005 09:11:
> On Fri, 2005-04-29 at 11:18 -0400, Joshua Baker-LePain wrote:
> > Err, really?  I saw exactly the opposite.  Now, this was on centos 4,
> > but
> > these numbers are for a software RAID0 across 2 9500-12 cards in 11
> > disk
> > RAID5 mode.  I'd also done 'blockdev --setra 16384' on both 3ware
> > devices, and this is with a kernel modified to include XFS:
>
> I can't help but wonder if the software RAID 0 is interfering with your
> setup.  Any chance you can test w/out the software RAID 0 involved?
> Just a straight RAID 5 across 11 disks?

Just last night I did essentially that on my system with a 9500S-12 with 
11-disk hw RAID5 + hot spare.  The command I ran was:

  sync ; time dd if=/dev/zero of=/scratch1/8G-2 bs=1M count=8192 ; time sync

Typical rate for the dd was 12-15MB/sec, right in line with what Joshua saw 
(he saw roughly double this for two such arrays RAID0'd together).  This rate 
is terrible, no? :)  I chose to write an 8GB file because the system memory 
is 4GB.  I made several other observations on this system; I made lengthy 
comments on https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=121434.

I can run other tests; I'm open to suggestions.  Since this box has a second 
identical array, I plan to try that one with sw RAID5 instead of hw RAID5.

My test was to an XFS filesystem, using a RHEL4 kernel modified to have XFS 
enabled (much like Joshua, I suspect).  I don't have numbers for earlier 
firmware/drivers.

David