From owner-freebsd-questions@FreeBSD.ORG Wed Mar 6 05:47:51 2013 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 2BBDBC90 for ; Wed, 6 Mar 2013 05:47:51 +0000 (UTC) (envelope-from gezeala@gmail.com) Received: from mail-la0-x231.google.com (mail-la0-x231.google.com [IPv6:2a00:1450:4010:c03::231]) by mx1.freebsd.org (Postfix) with ESMTP id 88B6322B for ; Wed, 6 Mar 2013 05:47:50 +0000 (UTC) Received: by mail-la0-f49.google.com with SMTP id fs13so6832389lab.8 for ; Tue, 05 Mar 2013 21:47:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:mime-version:in-reply-to:references:from:date:message-id :subject:to:cc:content-type; bh=ZwNQBy6Q8QjcLjNvKAZ5u25YxXPdITvJSlgvRATSG6g=; b=KMsGZL/P3+2u9yv1GosNxLsjqnmLj6dvtZsaYf+U99g/vxyOfkmEfwGksgqHGb2inP S7y9fbfe8RxZcN584BAVJ9VYvRKfRDVU6oBT7CDu1edcHAJtH8driZPQBH7OGHCgbDtr oUcqcfxumunIrEnAPdgNFEimXP9loZeVxtQ8WBREVRCdgdCoM7WKslcU1V5XzjHYXXMc N0OetkcLfvn5TRj+qde1Extp7AMexZdJB7e/aYvz8nRnIi3IKua5Hxp5KXj1ZphEgoXp Q6s3oKXAsjWQ9Ze/GqfcZ1bAN58eioi6MjC2N3bdbRkbb1G6qsCoGWiCsTWy4J+6SqNb bm9w== X-Received: by 10.112.83.67 with SMTP id o3mr6991556lby.7.1362548869529; Tue, 05 Mar 2013 21:47:49 -0800 (PST) MIME-Version: 1.0 Received: by 10.114.23.106 with HTTP; Tue, 5 Mar 2013 21:47:09 -0800 (PST) In-Reply-To: References: From: =?ISO-8859-1?Q?Gezeala_M=2E_Bacu=F1o_II?= Date: Tue, 5 Mar 2013 21:47:09 -0800 Message-ID: Subject: Re: Tuning ZFS ARC for 512GB Memory To: "Reed A. Cartwright" Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.14 Cc: freebsd-questions@freebsd.org X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 06 Mar 2013 05:47:51 -0000 Try to read through the email thread I have started and specifically posts (replies) by alc: http://lists.freebsd.org/pipermail/freebsd-performance/2012-August/thread.html#4640 I have followed his suggestions, and with the arc_max setting I used we still have on average free RAM ~137GB. HTH. On Tue, Mar 5, 2013 at 6:36 PM, Reed A. Cartwright wrote: > I have a 512GB memory system that has a 480GB (or so) L2ARC, and a > raidz2 storage pool. No dedup or compression is enabled. Although, I > will enable compression in the future. > > By default vfs.zfs.arc_max is about 300GB and the L2ARC is hardly touched. > > I've seen a couple hints recently on the mailing lists that having too > big of an ARC can be a performance hit because it takes a long time to > inspect it when something needs to integrate over the entries. > > I've also had issues with running 9.1 on this machine due to zfs > deadlocks or stalls and am currently "stuck" using 9.0 with no issue. > > So, I was wondering if shrinking the ARC would potentially help and > what should I shrink it to? > > I am thinking about setting vfs.zfs.arc_max to 64GB. > > Does anyone have an opinion? > > > -- > Reed A. Cartwright, PhD > Assistant Professor of Genomics, Evolution, and Bioinformatics > School of Life Sciences > Center for Evolutionary Medicine and Informatics > The Biodesign Institute > Arizona State University > _______________________________________________ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to " > freebsd-questions-unsubscribe@freebsd.org" >