From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45130) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dv0fi-0005aR-7z for qemu-devel@nongnu.org; Thu, 21 Sep 2017 08:33:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dv0ff-0001sC-2O for qemu-devel@nongnu.org; Thu, 21 Sep 2017 08:33:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51484) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dv0fe-0001rY-Sh for qemu-devel@nongnu.org; Thu, 21 Sep 2017 08:33:35 -0400 Date: Thu, 21 Sep 2017 13:33:27 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20170921123326.GD2717@work-vm> References: <1505839684-10046-1-git-send-email-a.perevalov@samsung.com> <1505839684-10046-9-git-send-email-a.perevalov@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1505839684-10046-9-git-send-email-a.perevalov@samsung.com> Subject: Re: [Qemu-devel] [PATCH v10 08/10] migration: postcopy_blocktime documentation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexey Perevalov Cc: qemu-devel@nongnu.org, i.maximets@samsung.com, peterx@redhat.com, eblake@redhat.com, quintela@redhat.com, heetae82.ahn@samsung.com * Alexey Perevalov (a.perevalov@samsung.com) wrote: > Reviewed-by: Dr. David Alan Gilbert > Signed-off-by: Alexey Perevalov Although it does have my R-b it might be worth adding some clarification that it's a measure of when *all* cpus are blocked and so isn't a total measure of impact of postcopy (when blocking some of them). Dave > --- > docs/devel/migration.txt | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/docs/devel/migration.txt b/docs/devel/migration.txt > index 1b940a8..4b625ca 100644 > --- a/docs/devel/migration.txt > +++ b/docs/devel/migration.txt > @@ -402,6 +402,16 @@ will now cause the transition from precopy to postcopy. > It can be issued immediately after migration is started or any > time later on. Issuing it after the end of a migration is harmless. > > +Blocktime is a postcopy live migration metric, intended to show > +how long the vCPU was in state of interruptable sleep due to pagefault. > +This value is calculated on destination side. > +To enable postcopy blocktime calculation, enter following command on destination > +monitor: > + > +migrate_set_capability postcopy-blocktime on > + > +Postcopy blocktime can be retrieved by query-migrate qmp command. > + > Note: During the postcopy phase, the bandwidth limits set using > migrate_set_speed is ignored (to avoid delaying requested pages that > the destination is waiting for). > -- > 1.9.1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK