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Date: Mon, 23 Mar 2015 15:00:05 +0000
Message-ID: <CAJSP0QUOTra0shpnuo1jrRebdVfnt2cpnpT2EGaCsPxY6iat2A@mail.gmail.com>
From: Stefan Hajnoczi <stefanha@gmail.com>
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Subject: Re: [Qemu-devel] [PATCH v2] block: Switch to host monotonic clock
	for IO throttling
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Fam Zheng <famz@redhat.com>, Alberto Garcia <berto@igalia.com>, qemu-devel <qemu-devel@nongnu.org>, Stefan Hajnoczi <stefanha@redhat.com>

On Mon, Mar 23, 2015 at 2:49 PM, Paolo Bonzini <pbonzini@redhat.com> wrote:
> On 23/03/2015 15:28, Stefan Hajnoczi wrote:
>> I'd like to know what problems exactly this patch fixes.  The test
>> case for throttling actually relies on the virtual clock so it can be
>> stepped deterministically.  What other legitimate cases are there
>> where throttling is used outside a running qemu-system process?
>
> Alberto brought up block jobs.  It is debatable whether block jobs
> should be stopped while the VM is.

This patch is unrelated to block jobs.  Block jobs use their own
ratelimiting mechanism and the realtime clock (not vm clock).

Stefan