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Date: Thu, 29 Mar 2012 17:10:17 +0100
From: Chris Webb <chris@arachsys.com>
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Subject: Re: [Qemu-devel] [PATCH 0/2] ide: convert pio code path to
 asynchronous I/O
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Richard Davies <richard@arachsys.com>, Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>, qemu-devel@nongnu.org, Zhi Yong Wu <wuzhy@cn.ibm.com>, Paolo Bonzini <pbonzini@redhat.com>

Stefan Hajnoczi <stefanha@gmail.com> writes:

> Thanks for trying it out.
> 
> Regarding the guest kernel errors, they may be timeouts.  The guest
> may consider the IDE controller buggy/dead due to how long requests
> take to complete under severe throttling.  There's not much that can
> be done about that, I think.  If you think the guest errors are due to
> something else though, please post the error messages.

I'm sure you're right that they're standard timeouts. We see exactly the
same behaviour when a guest is on a very heavily contended disk with slow
access because of that.

Best wishes,

Chris.