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Re: [Xen-users] Re: Performance Issues: I/O Wait

To: Nick Couchman <Nick.Couchman@xxxxxxxxx>
Subject: Re: [Xen-users] Re: Performance Issues: I/O Wait
From: Stephan Seitz <s.seitz@xxxxxxxxxxxx>
Date: Wed, 24 Oct 2007 04:03:44 +0200
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Nick Couchman schrieb:
> Hi, again...haven't had any responses to this, yet.
> Thanks,
> Nick


have you tried to pin your vCPU's to dedicated Cores?
It might be suboptimal if a domU uses.. say core 0 of
cpu 0 and core 0 of cpu 1 ... or anything not on the
same cpu.
e.g. use the second cpu on a 2x dualcore system
count starts at 0.
cpus = [ 2,3 ]

If your domU is bridged, you might try to disable
transmission checksums on the NIC's.
ethtool -K [nicname] tx off

Anyway, you mentioned high I/O latency due to network
issues. Is your domU using some kind of NFS or something?
Btw. I might missed this part, but are you using PV or
HVM guests?


Stephan Seitz
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