From owner-freebsd-stable@FreeBSD.ORG Thu Feb 9 01:20:40 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C9D321065672; Thu, 9 Feb 2012 01:20:40 +0000 (UTC) (envelope-from 000.fbsd@quip.cz) Received: from elsa.codelab.cz (elsa.codelab.cz [94.124.105.4]) by mx1.freebsd.org (Postfix) with ESMTP id 1E85F8FC0C; Thu, 9 Feb 2012 01:20:40 +0000 (UTC) Received: from elsa.codelab.cz (localhost [127.0.0.1]) by elsa.codelab.cz (Postfix) with ESMTP id 32F842842E; Thu, 9 Feb 2012 02:20:38 +0100 (CET) Received: from [192.168.1.2] (ip-86-49-61-235.net.upcbroadband.cz [86.49.61.235]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by elsa.codelab.cz (Postfix) with ESMTPSA id 7931128424; Thu, 9 Feb 2012 02:20:36 +0100 (CET) Message-ID: <4F331F63.60707@quip.cz> Date: Thu, 09 Feb 2012 02:20:35 +0100 From: Miroslav Lachman <000.fbsd@quip.cz> User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9.1.19) Gecko/20110420 Lightning/1.0b1 SeaMonkey/2.0.14 MIME-Version: 1.0 To: Artem Belevich References: <4F310115.3070507@FreeBSD.org> <4F310C5A.6070400@norma.perm.ru> <4F310E75.7090301@FreeBSD.org> <4F3144A9.2000505@norma.perm.ru> <4F314892.50806@FreeBSD.org> <4F314B5B.100@norma.perm.ru> <4F3186C6.8000904@FreeBSD.org> <4F324F10.2060508@norma.perm.ru> <4F32DB30.6020600@FreeBSD.org> <4F330F38.3010806@quip.cz> <20120209002835.GA29400@icarus.home.lan> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Andriy Gapon , "Eugene M. Zheganin" , freebsd-stable , mm@freebsd.org, Jeremy Chadwick Subject: Re: zfs arc and amount of wired memory X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 09 Feb 2012 01:20:40 -0000 Artem Belevich wrote: > On Wed, Feb 8, 2012 at 4:28 PM, Jeremy Chadwick > wrote: >> On Thu, Feb 09, 2012 at 01:11:36AM +0100, Miroslav Lachman wrote: > ... >>> ARC Size: >>> Current Size: 1769 MB (arcsize) >>> Target Size (Adaptive): 512 MB (c) >>> Min Size (Hard Limit): 512 MB (zfs_arc_min) >>> Max Size (Hard Limit): 3584 MB (zfs_arc_max) >>> >>> The target size is going down to the min size and after few more >>> days, the system is so slow, that I must reboot the machine. Then it >>> is running fine for about 107 days and then it all repeat again. >>> >>> You can see more on MRTG graphs >>> http://freebsd.quip.cz/ext/2012/2012-02-08-kiwi-mrtg-12-15/ >>> You can see links to other useful informations on top of the page >>> (arc_summary, top, dmesg, fs usage, loader.conf) >>> >>> There you can see nightly backups (higher CPU load started at >>> 01:13), otherwise the machine is idle. >>> >>> It coresponds with ARC target size lowering in last 5 days >>> http://freebsd.quip.cz/ext/2012/2012-02-08-kiwi-mrtg-12-15/local_zfs_arcstats_size.html >>> >>> And with ARC metadata cache overflowing the limit in last 5 days >>> http://freebsd.quip.cz/ext/2012/2012-02-08-kiwi-mrtg-12-15/local_zfs_vfs_meta.html >>> >>> I don't know what's going on and I don't know if it is something >>> know / fixed in newer releases. We are running a few more ZFS >>> systems on 8.2 without this issue. But those systems are in >>> different roles. >> >> This sounds like the... damn, what is it called... some kind of internal >> "counter" or "ticks" thing within the ZFS code that was discovered to >> only begin happening after a certain period of time (which correlated to >> some number of days, possibly 107). I'm sorry that I can't be more >> specific, but it's been discussed heavily on the lists in the past, and >> fixes for all of that were committed to RELENG_8. Thank you for your quick response. I am glad that it is fixed in 8.x. So I will upgrade this last old machine in few weeks. :) >> I wish I could >> remember the name of the function or macro or variable name it pertained >> to, something like LTHAW or TLOCK or something like that. I would say >> "I don't know why I can't remember", but I do know why I can't remember: >> because I gave up trying to track all of these problems. >> >> Does someone else remember this issue? CC'ing Martin who might remember >> for certain. > > It's LBOLT. :-) > > And there was more than one related integer overflow. One of them > manifested itself as L2ARC feeding thread hogging CPU time after about > a month of uptime. Another one caused issue with ARC reclaim after 107 > days. See more details in this thread: > > http://lists.freebsd.org/pipermail/freebsd-fs/2011-May/011584.html Yes, it is exactly this problem. Thank you for the link to this thread. I am subscribed to freebsd-fs@ and I am reading it almost daily, but I missed this one! Thanks to both of you! Miroslav Lachman