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Date: Fri, 8 Mar 2019 19:28:30 +0000
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Message-ID: <20190308192829.GL2834@work-vm>
References: <20190227110812.2185-1-quintela@redhat.com>
	<20190227110812.2185-4-quintela@redhat.com>
	<20190306152812.GF2727@work-vm> <87o96m3m2o.fsf@trasno.org>
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Subject: Re: [Qemu-devel] [PATCH v3 3/8] multifd: Create new
 next_packet_size field
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To: Juan Quintela <quintela@redhat.com>
Cc: qemu-devel@nongnu.org, Markus Armbruster <armbru@redhat.com>, Eric Blake <eblake@redhat.com>, Thomas Huth <thuth@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, Laurent Vivier <lvivier@redhat.com>

* Juan Quintela (quintela@redhat.com) wrote:
> "Dr. David Alan Gilbert" <dgilbert@redhat.com> wrote:
> > * Juan Quintela (quintela@redhat.com) wrote:
> >> We need to send this field when we add compression support.  As we are
> >> still on x- stage, we can do this kind of changes.
> >> 
> >> Signed-off-by: Juan Quintela <quintela@redhat.com>
> >
> > OK, so that kind of makes sense - in that what you want to do is read
> > the whole compressed chunk in one go.
> >
> > Consider it might be a good idea to add some spare entries here;
> > say a uint64_t dummy[4] so that if you need any more fields in the
> > future it'll be easy to add them without breaking compatibility.
> 
> We have a version field, so ... we can handle it relatively gratiously,
> but I see your point.
> 
> How many?

<rolls dice>

4

Now don't use them all at once!

Dave
 
> Later, Juan.
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK