From owner-freebsd-current@FreeBSD.ORG Fri Jul 9 23:22:17 2010 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A7997106564A; Fri, 9 Jul 2010 23:22:17 +0000 (UTC) (envelope-from peterjeremy@acm.org) Received: from mail11.syd.optusnet.com.au (mail11.syd.optusnet.com.au [211.29.132.192]) by mx1.freebsd.org (Postfix) with ESMTP id 366E98FC0C; Fri, 9 Jul 2010 23:22:16 +0000 (UTC) Received: from server.vk2pj.dyndns.org (c211-30-160-13.belrs4.nsw.optusnet.com.au [211.30.160.13]) by mail11.syd.optusnet.com.au (8.13.1/8.13.1) with ESMTP id o69NMDE1017037 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sat, 10 Jul 2010 09:22:14 +1000 X-Bogosity: Ham, spamicity=0.000000 Received: from server.vk2pj.dyndns.org (localhost.vk2pj.dyndns.org [127.0.0.1]) by server.vk2pj.dyndns.org (8.14.4/8.14.4) with ESMTP id o69NMAWX002124; Sat, 10 Jul 2010 09:22:10 +1000 (EST) (envelope-from peter@server.vk2pj.dyndns.org) Received: (from peter@localhost) by server.vk2pj.dyndns.org (8.14.4/8.14.4/Submit) id o69NMAX9002123; Sat, 10 Jul 2010 09:22:10 +1000 (EST) (envelope-from peter) Date: Sat, 10 Jul 2010 09:22:10 +1000 From: Peter Jeremy To: Martin Matuska Message-ID: <20100709232210.GA1973@server.vk2pj.dyndns.org> References: <4C31C71C.2010606@FreeBSD.org> <20100708200446.GA33822@server.vk2pj.dyndns.org> <4C364379.6020608@FreeBSD.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="3MwIy2ne0vdjdPXF" Content-Disposition: inline In-Reply-To: <4C364379.6020608@FreeBSD.org> X-PGP-Key: http://members.optusnet.com.au/peterjeremy/pubkey.asc User-Agent: Mutt/1.5.20 (2009-06-14) Cc: freebsd-current@FreeBSD.org Subject: Re: [CFT] ZFS v15 patch (version 3) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 09 Jul 2010 23:22:17 -0000 --3MwIy2ne0vdjdPXF Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 2010-Jul-08 23:30:33 +0200, Martin Matuska wrote: >> Looking at the patchset, the most critical issue (IMHO) that doesn't >> appear to have been addressed is the interaction between ZFS ARC and >> the VM cache used by UFS/NFS: arc_memory_throttle() is still making >> decisions solely on the amount of "free" memory, without considering >> "inactive" or "cache". I am running a slight variant of a patch by =2E.. >Regarding ARC, you might want to try the revision 209227 from head that >is scheduled for MFC on 18.7.2010: >http://people.freebsd.org/~mm/patches/zfs/head-12636.patch That patch appears to address issues with unreasonable arc sizing but doesn't alter the throttling algorithm: FreeBSD's "traditional" VM management algorithm (used by everything except ZFS) minimises space marked as "free" by preferentially keeping cached data in the "cache" or "inactive" queues. ZFS uses its own caching which solely uses the "free" list to determine memory availability. This means ZFS can't apply any pressure to the FreeBSD VM system and runs in a virtually permanent state of memory starvation. In any case, I have applied that patch as it appears useful. --=20 Peter Jeremy --3MwIy2ne0vdjdPXF Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (FreeBSD) iEYEARECAAYFAkw3ryIACgkQ/opHv/APuIdsYQCfQ/VX6wnrJKrhUO0LA/NDvG7A 6qcAoLavhmrdqcEyXgNU57ytudv/0sGV =o5Cf -----END PGP SIGNATURE----- --3MwIy2ne0vdjdPXF--