From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758770Ab2JXUcj (ORCPT ); Wed, 24 Oct 2012 16:32:39 -0400 Received: from mga01.intel.com ([192.55.52.88]:49536 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757886Ab2JXUch (ORCPT ); Wed, 24 Oct 2012 16:32:37 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,642,1344236400"; d="asc'?scan'208";a="239733163" Date: Wed, 24 Oct 2012 23:33:29 +0300 From: "Kirill A. Shutemov" To: Andrew Morton Cc: "Kirill A. Shutemov" , Andrea Arcangeli , linux-mm@kvack.org, Andi Kleen , "H. Peter Anvin" , linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 10/10] thp: implement refcounting for huge zero page Message-ID: <20121024203329.GA24716@otc-wbsnb-06> References: <20121018164502.b32791e7.akpm@linux-foundation.org> <20121018235941.GA32397@shutemov.name> <20121023063532.GA15870@shutemov.name> <20121022234349.27f33f62.akpm@linux-foundation.org> <20121023070018.GA18381@otc-wbsnb-06> <20121023155915.7d5ef9d1.akpm@linux-foundation.org> <20121023233801.GA21591@shutemov.name> <20121024122253.5ecea992.akpm@linux-foundation.org> <20121024194552.GA24460@otc-wbsnb-06> <20121024132552.5f9a5f5b.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="y0ulUmNC+osPPQO6" Content-Disposition: inline In-Reply-To: <20121024132552.5f9a5f5b.akpm@linux-foundation.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --y0ulUmNC+osPPQO6 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Oct 24, 2012 at 01:25:52PM -0700, Andrew Morton wrote: > On Wed, 24 Oct 2012 22:45:52 +0300 > "Kirill A. Shutemov" wrote: >=20 > > On Wed, Oct 24, 2012 at 12:22:53PM -0700, Andrew Morton wrote: > > >=20 > > > I'm thinking that such a workload would be the above dd in parallel > > > with a small app which touches the huge page and then exits, then gets > > > executed again. That "small app" sounds realistic to me. Obviously > > > one could exercise the zero page's refcount at higher frequency with a > > > tight map/touch/unmap loop, but that sounds less realistic. It's wor= th > > > trying that exercise as well though. > > >=20 > > > Or do something else. But we should try to probe this code's > > > worst-case behaviour, get an understanding of its effects and then > > > decide whether any such workload is realisic enough to worry about. > >=20 > > Okay, I'll try few memory pressure scenarios. >=20 > Thanks. >=20 > > Meanwhile, could you take patches 01-09? Patch 09 implements simpler > > allocation scheme. It would be nice to get all other code tested. > > Or do you see any other blocker? >=20 > I think I would take them all, to get them tested while we're still > poking at the code. It's a matter of getting my lazy ass onto reviewing > the patches. >=20 > The patches have a disturbing lack of reviewed-by's, acked-by's and > tested-by's on them. Have any other of the MM lazy asses actually > spent some time with them yet? Andrea Revieved-by previous version of the patchset, but I've dropped the tag after rebase to v3.7-rc1 due not-so-trivial conflicts. Patches 2, 3, 4, 7, 10 had conflicts. Mostly due new MMU notifiers interface. I mentioned that in cover letter. --=20 Kirill A. Shutemov --y0ulUmNC+osPPQO6 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJQiFCYAAoJEAd+omnVudOMw3sQAIcyQEn6ijiGBZvfOr2Ui6k1 1eOdG61OmPjla2g4NZLmArK+8LAxZq0SQxmfl9TTOXhbBaJxp8tsFNuhvk/OgC1m BqOlQWmQ0lsKxgzSsO9azbeCWIdB85VopeEZtUzdFQqXiuknbL0Lofy+zrouRYJg rd+jNsgtNOU5yqQg4u+dj6UtQNH/kVFlOlAIOPHwKNOnIkgd7QpPk4nCGx7w0YEI ycYwhc9p+DPuSAst27udp+s2uQD5xhiMSDORrJbYZ3lpn5sZjpMrAXoZuqWHrCif +iEJHe/V4DxEeAOXxpSsrwaflDqlNaOKlv0oN5Qp6ryps+BGUQi08ijFF6dHzf5b 2XyV2/Ln8+DH3xAXV3N7no9x63rSvZwqZDn/TjL+wLbFZRhGq2ITzuTk5gWbljBY zX+9k5ZYo2HOOg/1A9lyVaYnxTUWzMdeEwsGBebaDcThDVEk/yDsT54ZX7mnbqNv 4WqBNIeDJ9CwkW39uQ6/HtgQcAaKZuCYSG871vSfVmVFhM2c8Kp6NC2IXcWFJRg8 g5jvSfr32fZbbgbd1+x9Anl3XwF+hdITPZjewn/Vk7czoTfL4a2rrNr5CtQlG63+ laxGBtzilCuqs9+cRGEaa6Ar8nNIp3HAMTrTqO7uLjOp5yMO9uWQolKIY33TjG3n ZRH8ur3YvPAu4UICPDcK =lpHO -----END PGP SIGNATURE----- --y0ulUmNC+osPPQO6--