From owner-freebsd-fs@FreeBSD.ORG Mon Oct 12 08:32:29 2009 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 35BD4106568B; Mon, 12 Oct 2009 08:32:29 +0000 (UTC) (envelope-from bra@fsn.hu) Received: from people.fsn.hu (people.fsn.hu [195.228.252.137]) by mx1.freebsd.org (Postfix) with ESMTP id 87BCB8FC2A; Mon, 12 Oct 2009 08:32:27 +0000 (UTC) Received: by people.fsn.hu (Postfix, from userid 1001) id 929E4183787; Mon, 12 Oct 2009 10:32:25 +0200 (CEST) X-CRM114-Version: 20090423-BlameSteveJobs ( TRE 0.7.6 (BSD) ) MF-ACE0E1EA [pR: 20.9900] X-CRM114-CacheID: sfid-20091012_10322_3B663058 X-CRM114-Status: Good ( pR: 20.9900 ) Message-ID: <4AD2E998.8090409@fsn.hu> Date: Mon, 12 Oct 2009 10:32:24 +0200 From: Attila Nagy User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.23) Gecko/20090817 Thunderbird/2.0.0.23 Mnenhy/0.7.6.0 MIME-Version: 1.0 To: "K. Macy" References: <4AC1E540.9070001@fsn.hu> <4AC5B2C7.2000200@fsn.hu> <20091002184526.GA1660@garage.freebsd.pl> <4ACDA5EA.2010600@fsn.hu> <4ACDDED0.2070707@fsn.hu> <20091008160718.GB2134@garage.freebsd.pl> <4AD2E118.2050202@fsn.hu> <47C0A3F4-6431-49E5-B780-FA162946C288@freebsd.org> In-Reply-To: <47C0A3F4-6431-49E5-B780-FA162946C288@freebsd.org> X-Stationery: 0.4.10 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.3 (people.fsn.hu); Mon, 12 Oct 2009 10:32:24 +0200 (CEST) Cc: freebsd-fs@FreeBSD.org, Pawel Jakub Dawidek Subject: Re: ARC size constantly shrinks, then ZFS slows down extremely 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: Mon, 12 Oct 2009 08:32:29 -0000 K. Macy wrote: >> >> The amd64 machine started to loose ARC memory again. See these: >> http://people.fsn.hu/~bra/freebsd/20091012-zfs-arcsize/zfs_mem-week.png >> http://people.fsn.hu/~bra/freebsd/20091012-zfs-arcsize/memory-week.png >> >> Your patch was active between 7 and 9. You can see that the ARC size >> was somewhat constant. >> On october 9, I installed Kip's modification, and ARC size started to >> decrease. >> BTW, previously (before october 7) I set the arc min size to 10-15GB >> (can't remember the exact value), but now it runs with the defaults >> (only the max size is set): >> vfs.zfs.arc_min: 3623878656 >> vfs.zfs.arc_max: 28991029248 >> >> As you can see, there are plenty of memory. This machine uses UFS as >> well (and writes it heavily), maybe that's what affects ZFS size, by >> caching a lot of stuff? >> > > Currently, the inactive page queue will grow until ARC is shrunk to > arc_min. > > > I think I'll probably spend some time making the ARC play better with > the page cache this week. Unfortunately, under heavy memory pressure > when competing with UFS the ARC will degrade to LRU, but I think that > is still an improvement over the current static sizing with low and > high water marks. Will setting ARC's minimum size help here? (I will try) For me, it's OK, and I think it's generally not a problem, if somebody uses UFS as well. Is it possible to merge the memory management of the two, or they are completely different beasts? Thanks,