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Date: Tue, 8 Sep 2015 12:11:44 +0200
From: Kevin Wolf <kwolf@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH RFC 0/5] disk deadlines
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To: Fam Zheng <famz@redhat.com>
Cc: "Denis V. Lunev" <den@openvz.org>, qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>, "qemu-block@nongnu.org Raushaniya Maksudova" <rmaksudova@virtuozzo.com>

Am 08.09.2015 um 11:20 hat Fam Zheng geschrieben:
> [Cc'ing qemu-block@nongnu.org]
> 
> On Tue, 09/08 11:00, Denis V. Lunev wrote:
> > To avoid such situation this patchset introduces patch per-drive option
> > "disk-deadlines=on|off" which is unset by default.
> 
> The general idea sounds very nice. Thanks!
> 
> Should we allow user configuration on the timeout?  If so, the option should be
> something like "timeout-seconds=0,1,2...".  Also I think we could use werror
> and rerror to control the handling policy (whether to ignore/report/stop on
> timeout).

Yes, I think the timeout needs to be configurable. However, the only
action that makes sense is stop. Everything else would be unsafe because
the running request could still complete at a later point.

Another question I have related to safety is whether (and how) you can
migrate away from a host that has been stopped because of a timeout. I
guess migration needs to be blocked then?

Kevin