From owner-freebsd-stable@FreeBSD.ORG Tue Feb 7 10:46:51 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 8983F106564A for ; Tue, 7 Feb 2012 10:46:51 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id D50518FC1A for ; Tue, 7 Feb 2012 10:46:50 +0000 (UTC) Received: from porto.starpoint.kiev.ua (porto-e.starpoint.kiev.ua [212.40.38.100]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id MAA17192; Tue, 07 Feb 2012 12:46:47 +0200 (EET) (envelope-from avg@FreeBSD.org) Received: from localhost ([127.0.0.1]) by porto.starpoint.kiev.ua with esmtp (Exim 4.34 (FreeBSD)) id 1RuiZS-000OEJ-Mb; Tue, 07 Feb 2012 12:46:46 +0200 Message-ID: <4F310115.3070507@FreeBSD.org> Date: Tue, 07 Feb 2012 12:46:45 +0200 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:10.0) Gecko/20120202 Thunderbird/10.0 MIME-Version: 1.0 To: "Eugene M. Zheganin" References: <4F30E284.8080905@norma.perm.ru> In-Reply-To: <4F30E284.8080905@norma.perm.ru> X-Enigmail-Version: 1.3.5 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-stable 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: Tue, 07 Feb 2012 10:46:51 -0000 on 07/02/2012 10:36 Eugene M. Zheganin said the following: > Hi. > > I have a server with 9.0/amd64 and 4 Gigs of RAM. > Today's questions are about the amount of memory in 'wired' state and the ARC size. > > If I use the script from http://wiki.freebsd.org/ZFSTuningGuide , it says: > > ===Cut=== > ARC Size: 12.50% 363.14 MiB > Target Size: (Adaptive) 12.50% 363.18 MiB > Min Size (Hard Limit): 12.50% 363.18 MiB > Max Size (High Water): 8:1 2.84 GiB > ===Cut=== > > At the same time I have 3500 megs in wired state: > > ===Cut=== > Mem: 237M Active, 36M Inact, 3502M Wired, 78M Cache, 432K Buf, 37M Free > ===Cut=== > > First question - what is the actual size of ARC, and how can it be determined ? > Solaris version of the script is more comprehensive (ran on Solaris): > > ===Cut=== > ARC Size: > Current Size: 6457 MB (arcsize) > Target Size (Adaptive): 6457 MB (c) > Min Size (Hard Limit): 2941 MB (zfs_arc_min) > Max Size (Hard Limit): 23534 MB (zfs_arc_max) > ===Cut=== Please try sysutils/zfs-stats; zfs-stats -a output should provide a good overview of the state and configuration of the system. > The arcstat script makes me think that the ARC size is about 380 megs indeed: > > ===Cut=== > Time read miss miss% dmis dm% pmis pm% mmis mm% size tsize > 14:33:35 170M 7466K 4 7466K 4 192 78 793K 3 380M 380M > ===Cut=== > > Second question: if the size is 363 Megs, why do I have 3500 Megs in wired > state? From my experience this is directly related to the zfs, but 380 megs its > like about ten times smaller than 3600 megs. At the same time I have like 700 > Megs in swap, so my guess - zfs isn't freeing memory for current needs that easily. > > Yeah, I can tune it down, but I just would like to know what is happening on an > untuned machine. -- Andriy Gapon