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Date: Wed, 14 Nov 2012 09:45:09 +0100
From: Stefan Hajnoczi <stefanha@gmail.com>
Message-ID: <20121114084509.GB23826@stefanha-thinkpad.redhat.com>
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Subject: Re: [Qemu-devel] [RFC] libqblock OOM issue
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To: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Anthony Liguori <aliguori@us.ibm.com>, qemu-devel <qemu-devel@nongnu.org>, Blue Swirl <blauwirbel@gmail.com>, Paolo Bonzini <pbonzini@redhat.com>

On Wed, Nov 14, 2012 at 11:50:06AM +0800, Wenchao Xia wrote:
>   In order to resolve OOM issue, I am trying wrap all APIs using
> sunrpc, need some suggestion before coding.

Is the client/server approach really necessary or can you write a
library that invokes qemu-nbd/qemu-img?

If there is a startup cost problem with qemu-img it may be possible to
add an interactive mode (like qemu-io) where qemu-img stays open and
responds to commands (maybe in JSON encoding).

The difference between this and the RPC approach is that you can write a
relatively thin NBD and qemu-img library with the tools that already
exist today.

Stefan