Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764988AbXILJBT (ORCPT ); Wed, 12 Sep 2007 05:01:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763313AbXILJBF (ORCPT ); Wed, 12 Sep 2007 05:01:05 -0400 Received: from viefep18-int.chello.at ([213.46.255.22]:15750 "EHLO viefep34-int.chello.at" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752857AbXILJBE (ORCPT ); Wed, 12 Sep 2007 05:01:04 -0400 Subject: Re: [PATCH 00/23] per device dirty throttling -v10 From: Peter Zijlstra To: John Stoffel Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, miklos@szeredi.hu, akpm@linux-foundation.org, neilb@suse.de, dgc@sgi.com, tomoki.sekiyama.qu@hitachi.com, nikita@clusterfs.com, trond.myklebust@fys.uio.no, yingchao.zhou@gmail.com, richard@rsk.demon.co.uk, torvalds@linux-foundation.org In-Reply-To: <18151.20356.862163.430265@stoffel.org> References: <20070911195350.825778000@chello.nl> <18151.20356.862163.430265@stoffel.org> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-CJuUtTUukrRDlkmrjFkk" Date: Wed, 12 Sep 2007 11:00:59 +0200 Message-Id: <1189587659.21778.104.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.10.1 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1470 Lines: 45 --=-CJuUtTUukrRDlkmrjFkk Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Tue, 2007-09-11 at 22:31 -0400, John Stoffel wrote: I hope the snipped questions were sufficiently answered in the other mail. If not, holler :-) > Peter> 3 is done by also scaling the dirty limit proportional to the > Peter> current task's recent dirty rate. >=20 > Do you mean task or device here? I'm just wondering how well this > works with a bunch of devices with wildly varying speeds. =20 Task. What I do is modify the limit like this: current_limit =3D dirty_limit * p(bdi_writeout) * (1 - p(task_dirty)/8) Where the p() values are [0, 1]. By including the inverse of the task dirty rate one gets that tasks that are more agressive dirtiers get throttled more aggressively, whereas tasks that occasionally dirty a page get a little more room. --=-CJuUtTUukrRDlkmrjFkk Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQBG56rLXA2jU0ANEf4RAgoNAJ9oZ6x4zIh+sgiFt+rcWGJBapCQ5gCcCKu5 qn++C+cgC9zEBLqaND5CAGI= =JXs2 -----END PGP SIGNATURE----- --=-CJuUtTUukrRDlkmrjFkk-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/