From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48804) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xol4r-0006nk-Pp for qemu-devel@nongnu.org; Wed, 12 Nov 2014 22:28:11 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Xol4q-00022D-Ou for qemu-devel@nongnu.org; Wed, 12 Nov 2014 22:28:09 -0500 Received: from ozlabs.org ([2401:3900:2:1::2]:44987) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xol4q-000220-Er for qemu-devel@nongnu.org; Wed, 12 Nov 2014 22:28:08 -0500 Date: Thu, 13 Nov 2014 14:01:05 +1100 From: David Gibson Message-ID: <20141113030105.GD7291@voom.fritz.box> References: <1412358473-31398-1-git-send-email-dgilbert@redhat.com> <1412358473-31398-43-git-send-email-dgilbert@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="xB0nW4MQa6jZONgY" Content-Disposition: inline In-Reply-To: <1412358473-31398-43-git-send-email-dgilbert@redhat.com> Subject: Re: [Qemu-devel] [PATCH v4 42/47] Don't sync dirty bitmaps in postcopy List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Dr. David Alan Gilbert (git)" Cc: aarcange@redhat.com, yamahata@private.email.ne.jp, lilei@linux.vnet.ibm.com, quintela@redhat.com, cristian.klein@cs.umu.se, qemu-devel@nongnu.org, amit.shah@redhat.com, yanghy@cn.fujitsu.com --xB0nW4MQa6jZONgY Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Oct 03, 2014 at 06:47:48PM +0100, Dr. David Alan Gilbert (git) wrot= e: > From: "Dr. David Alan Gilbert" >=20 > Once we're in postcopy the source processors are stopped and memory > shouldn't change any more, so there's no need to look at the dirty > map. >=20 > There are two notes to this: > 1) If we do resync and a page had changed then the page would get > sent again, which the destination wouldn't allow (since it might > have also modified the page) > 2) Before disabling this I'd seen very rare cases where a page had been > marked dirtied although the memory contents are apparently identical It would be nice to understand how that happened. > Signed-off-by: Dr. David Alan Gilbert Otherwise, Reviewed-by: David Gibson --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --xB0nW4MQa6jZONgY Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJUZB7xAAoJEGw4ysog2bOSf8MP/ROa+INc97+uL/VVF5uIjVgN ZZV9bHE2L+ZXua5qis7PL9nG7mj4qNJr8V0bD8ez+UhtCn9CTS64iHuDtEdZzgb6 LhQjt+A4/NqSMUPYAx0slHX1RHtMhQWsYuos25HErXOQLGujnE5bQ+h940Vzw9pT NwmbuS/+5UwLA6FYFUPy8l5TGFCWCvcoUiv1n/ypD0aweJCSq8F25TgpQhWq8wwE Vm0nW7iN0XXdhLa/F6p3vYyg7x1R4xBPPAzRBZ56N4BWZaZLZIXrlaTdKTZAllD9 iRnX9sFsW5UWSiDIVwfEzu8vlIll5S5hKg3emV46/hylAnu7qaRpioRjpt9FZk5f koEnTgafihk8Hta3n4KE/DClTr0AexG2X+4s+XMhwnUXVu8tJTWHC9phqeMM9twy 9RUaqre/RantBlcvJ2c4J+gBN5vT0Fj2tDXbtfQo8SnJfWdFjeyTLE4NJsqlUyIo sIH/TTxoDgUNweLKzDd80hr7X9WBnukqodSBtLrc7OAHtD4qaZysRui4LS7L74JL TV4004t1TFIg2tetzQH5Mv/C91W1DTmNfCwMITmag+VtOtIao+NU+/oSgWKRGvbl tuILGZhKRVZN90r8HmXOw3q/XII62cJCIsi7z8ZiQ7dlN4FMwxrRboYNEAb6iVyG lIv0jYXW32ehyf2bjpne =cKmD -----END PGP SIGNATURE----- --xB0nW4MQa6jZONgY--