From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH] tcm_vhost: Add hotplug/hotunplug support
Date: Wed, 06 Mar 2013 18:41:47 +0100
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	<20130305121125.GA823@redhat.com>
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Cc: kvm@vger.kernel.org, "Michael S. Tsirkin" <mst@redhat.com>,
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	Stefan Hajnoczi <stefanha@redhat.com>
To: Asias He <asias@redhat.com>
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Il 06/03/2013 02:28, Asias He ha scritto:
>> > This can queue up quite a bit of memory if the handler thread
>> > is delayed, no? Can we limit the # of outstanding events?
>> > Will guest recover from a missed event?
> Hmm, good point. Will limit the number. The size of 'struct
> tcm_vhost_evt' is around 20 bytes. So if we limit it to 128, it is ~2.5K
> of memory.
> 
> Paolo, if we limit the number of outstanding events and set
> vs->vs_events_dropped, the guest will recover from a missed event, right?

Yes.  At least it should (it doesn't yet).

Paolo