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Re: [Xen-users] bad I/O performance with HP Smart Array RAID

To: DOGUET Emmanuel <Emmanuel.DOGUET@xxxxxxxx>
Subject: Re: [Xen-users] bad I/O performance with HP Smart Array RAID
From: Thomas Aeby <aeby@xxxxxxxxxx>
Date: Tue, 24 Feb 2009 17:20:15 +0100
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DOGUET Emmanuel wrote:
And what about the Write Cache on all your RAID card? On SmartArray P400i it's an option :/
 I have buy one for trying.

Well, I'd expect the RAID controller to deliver at least the throughput of a ATA-133 controller without the battery buffered write cache.

But it seems that I might have been a little too fast blaming this on Xen. Googling for cciss performance issues is quite enlightening. However, I haven't found a solution so far, though tuning a few driver parameters gave a few Megs/s more.

Best regards,
Thomas Aeby, Kirchweg 52, 1735 Giffers, Switzerland
Voice : (+41)26 4180040
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