From owner-freebsd-fs@FreeBSD.ORG Fri Dec 31 17:39:31 2010 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id D6E9C106564A for ; Fri, 31 Dec 2010 17:39:31 +0000 (UTC) (envelope-from freebsd-fs@m.gmane.org) Received: from lo.gmane.org (lo.gmane.org [80.91.229.12]) by mx1.freebsd.org (Postfix) with ESMTP id 6246E8FC23 for ; Fri, 31 Dec 2010 17:39:31 +0000 (UTC) Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1PYiwr-000128-Q7 for freebsd-fs@freebsd.org; Fri, 31 Dec 2010 18:39:29 +0100 Received: from host-174-44-170-66.hln-mt.client.bresnan.net ([174.44.170.66]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 31 Dec 2010 18:39:29 +0100 Received: from dsamms by host-174-44-170-66.hln-mt.client.bresnan.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 31 Dec 2010 18:39:29 +0100 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-fs@freebsd.org From: David Samms Date: Fri, 31 Dec 2010 10:39:09 -0700 Lines: 79 Message-ID: References: <4D1BCE34.4090601@nw-ds.com> <20101230085723.GA38391@tolstoy.tols.org> <8639pe55zj.fsf@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Complaints-To: usenet@dough.gmane.org X-Gmane-NNTP-Posting-Host: host-174-44-170-66.hln-mt.client.bresnan.net User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.1.16) Gecko/20101228 Thunderbird/3.0.11 In-Reply-To: <8639pe55zj.fsf@gmail.com> Subject: Re: 8.2-RC1 and ZFS X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 31 Dec 2010 17:39:32 -0000 On 12/31/10 08:14, Anonymous wrote: > David Samms writes: > > [...] >> The same test with ZFSv28 and ZFSv28 + tuning >> >> ZFSv28 >> ---------------------------------------------------------------------- >> dd if=/dev/zero of=big bs=1m count=6400 >> 6710886400 bytes transferred in 158.205268 secs (42418855 bytes/sec) >> >> OpenOffice 197sec >> MP3 skips >> XFCE4 popup menus took 5-15 seconds to appear >> >> >> ZFSv28 + tuning >> --vfs.zfs.txg.timeout="5" > > the tunable defaults to "5" in v28, see txg.c > > int zfs_txg_timeout = 5; /* max seconds worth of delta per txg */ > >> --vfs.zfs.txg.write_limit_override=268435456 > > No such tunable/sysctl. It was renamed to vfs.zfs.write_limit_override > in v28 (note ".txg." absence). > >> --kern.maxvnodes=250000 > >> ---------------------------------------------------------------------- >> dd if=/dev/zero of=big bs=1m count=6400 >> 6710886400 bytes transferred in 167.316444 secs (40108947 bytes/sec) >> >> OpenOffice 190sec >> No MP3 skips during "dd", but one skip while OpenOffice was starting >> XFCE4 popup menus took 2-13 seconds to appear Thank you for the correction. Please disregard my previous test results for ZFS+tuning. Below are the corrected results: ZFSv28 defaults + -- vfs.zfs.write_limit_override: 268435456 -- kern.maxvnodes=250000 ---------------------------------------------------------------------- dd if=/dev/zero of=big bs=1m count=6400 6710886400 bytes transferred in 254.771374 secs (26340818 bytes/sec) OpenOffice 82sec No Skips menus 0-1 sec ZFSv28 defaults + -- vfs.zfs.write_limit_override: 1073741824 -- kern.maxvnodes=250000 ---------------------------------------------------------------------- dd if=/dev/zero of=big bs=1m count=6400 6710886400 bytes transferred in 189.671025 secs (35381716 bytes/sec) OpenOffice 190sec No Skips menus 0-2 sec Setting vfs.zfs.write_limit_override: 268435456 significantly slows writes but make reads wonderful. Not ideal though. Setting vfs.zfs.write_limit_override: 1073741824 brings writes up to 87% of UFS+s and _dramatically_ improves GUI responsiveness. Very good setting for an old desktop machine. Being a ZFS novice, I would appreciate any links to tuning information. The default ZFS tuning do not seem good for a web-server or desktop which is fine, but guiding sysadmins to typical settings for their application would be helpful.