From owner-freebsd-stable@FreeBSD.ORG Fri Apr 29 02:40:08 2011 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 3125E1065675; Fri, 29 Apr 2011 02:40:08 +0000 (UTC) (envelope-from doconnor@gsoft.com.au) Received: from cain.gsoft.com.au (unknown [IPv6:2001:44b8:7c07:5581:266:e1ff:fe0c:8f16]) by mx1.freebsd.org (Postfix) with ESMTP id CA50E8FC20; Fri, 29 Apr 2011 02:40:06 +0000 (UTC) Received: from ur.gsoft.com.au (Ur.gsoft.com.au [203.31.81.44]) (authenticated bits=0) by cain.gsoft.com.au (8.14.4/8.14.3) with ESMTP id p3T2dxd2007270 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Fri, 29 Apr 2011 12:09:59 +0930 (CST) (envelope-from doconnor@gsoft.com.au) Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: text/plain; charset=us-ascii From: "Daniel O'Connor" In-Reply-To: Date: Fri, 29 Apr 2011 12:09:59 +0930 Content-Transfer-Encoding: quoted-printable Message-Id: References: <537A8F4F-A302-40F9-92DF-403388D99B4B@gsoft.com.au> <20110428195601.GA31807@icarus.home.lan> <20110429010829.GA36744@icarus.home.lan> To: Artem Belevich X-Mailer: Apple Mail (2.1084) X-Spam-Score: -2.51 () ALL_TRUSTED,BAYES_00,T_RP_MATCHES_RCVD X-Scanned-By: MIMEDefang 2.67 on 203.31.81.10 Cc: freebsd-stable List , Jeremy Chadwick Subject: Re: ZFS vs OSX Time Machine 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: Fri, 29 Apr 2011 02:40:08 -0000 On 29/04/2011, at 11:43, Artem Belevich wrote: > On Thu, Apr 28, 2011 at 6:08 PM, Jeremy Chadwick > wrote: >> I will note something, however: your ARC max is set to 3072MB, yet = Wired >> is around 4143MB. Do you have something running on this box that = takes >> up a lot of RAM? mysqld, etc..? I'm trying to account for the = "extra >> gigabyte" in Wired. "top -o res" might help here, but we'd need to = see >> the process list. >>=20 >> I'm thinking something else on your machine is also taking up Wired, >> because your arcstats shows: >>=20 >>> kstat.zfs.misc.arcstats.c: 3221225472 >>> kstat.zfs.misc.arcstats.c_min: 402653184 >>> kstat.zfs.misc.arcstats.c_max: 3221225472 >>> kstat.zfs.misc.arcstats.size: 3221162968 >>=20 >> Which is about 3072MB (there is always some degree of variance). >=20 > The difference is probably due to fragmentation (most of ARC > allocations are served from power-of-2 zones, if I'm not mistaken) + a > lot of wired memory sits in slab allocator caches (FREE column in > vmstat -z). On a system with ARC size of ~16G I regularly see ~22GB > wired. Ona smaller box I get about 7GB wired at around 5.5GB ARC size. This system also does double duty as a desktop PC so it gets a fair = hammering.. It did have 4GB of RAM but that was fairly terrible, 8GB is a lot better = though :) -- Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au "The nice thing about standards is that there are so many of them to choose from." -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C