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[Xen-devel] Re: poor domU VBD performance.

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Subject: [Xen-devel] Re: poor domU VBD performance.
From: peter bier <peter_bier@xxxxxx>
Date: Tue, 29 Mar 2005 15:27:29 +0000 (UTC)
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Ian Pratt <m+Ian.Pratt <at> cl.cam.ac.uk> writes:
> > Would you mind repeating these experiments with a 2.4 dom0 
> > and a 2.6domU
> > ?
> Also, please could you try exporting the device to the dom0 as a scsi
> device e.g. sda1 rather than ide device hde1 or hda1. [Yes, I know this
> shouldn't make any difference, but I have a suspicion it will.]
> Thanks,
> Ian


I will do the tests you asked for. but today is my wife's birthday, and I 
am already at home so I have no access to me test computers there. 

I have done some testing with the second, newer host with SATA Disks. The change
of the readahead quantity showed no effect on the reduced throughput. I do not
remember the exact ratio, but I think it was quite similar than with the ide 
disks and readahead of 256 sectors.

I will report on that tomorrow in a more detailed fashion. 

And I will do the tests with linux 2.4 as domU 


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