Re: [Qemu-devel] [PATCH for-3.0 4/4] tests: torture release-ram in postcopy test

[Peter Xu]

On Tue, Jul 24, 2018 at 12:42:06PM +0100, Dr. David Alan Gilbert wrote:
> * Peter Xu (address@hidden) wrote:
> > On Tue, Jul 24, 2018 at 11:25:24AM +0200, Juan Quintela wrote:
> > > Peter Xu <address@hidden> wrote:
> > > > The release-ram capability will run some extra code for postcopy to
> > > > release used ram right away, let's just turn that on for the postcopy
> > > > unix test always to torture that code path too to make sure release-ram
> > > > feature won't break again.  The recovery test needs to turn that off
> > > > since release-ram cannot coop with that.
> > > >
> > > > Signed-off-by: Peter Xu <address@hidden>
> > > 
> > > Reviewed-by: Juan Quintela <address@hidden>
> > 
> > Thanks.
> > 
> > > 
> > > But I think that the proper thing to do here is to have two tests.  One
> > > for postcopy and another for postcopy + release-ram.
> > 
> > Yeah I thought about it too, but I am not sure whether it'll worth it
> > to have a separate test for the release-ram feature (basically that's
> > some extra seconds for every unit test, even on relatively fast CPUs).
> > I did it this way since IMHO release-ram is mostly adding extra code
> > path to the postcopy logic, hence we should not miss much (or any) of
> > the old test path.  Ideally we should still cover all the postcopy
> > code path that we want to test.
> 
> It's worth being a bit careful, since I'm not sure if release-ram has
> ever been tested on hosts with larger page size; my suspicion is you
> might get a spew of errors on Power.

Oh I hope not.  If it happens, please feel free to drop this last
patch for 3.0.  Or I can provide a x86-only version if preferred.

Regards,

-- 
Peter Xu