From owner-freebsd-stable@FreeBSD.ORG Fri Nov 6 21:11:52 2009 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 EF5711065672 for ; Fri, 6 Nov 2009 21:11:52 +0000 (UTC) (envelope-from mloftis@wgops.com) Received: from juggler.wgops.com (juggler.wgops.com [204.11.247.41]) by mx1.freebsd.org (Postfix) with ESMTP id C4E998FC16 for ; Fri, 6 Nov 2009 21:11:52 +0000 (UTC) Received: by juggler.wgops.com (Postfix, from userid 65534) id 3E0CFA810E; Fri, 6 Nov 2009 14:11:52 -0700 (MST) X-Spam-ASN: X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on juggler.wgops.com X-Spam-Level: X-Spam-Status: No, score=-1.3 required=5.0 tests=ALL_TRUSTED, SARE_SUB_OBFU_OTHER autolearn=no version=3.2.5 Received: from [192.168.1.44] (host-72-174-39-176.msl-mt.client.bresnan.net [72.174.39.176]) by juggler.wgops.com (Postfix) with ESMTPSA id 12298A8070 for ; Fri, 6 Nov 2009 14:11:49 -0700 (MST) Date: Fri, 06 Nov 2009 14:11:54 -0700 From: Michael Loftis To: freebsd-stable@freebsd.org Message-ID: <94A540AC0E2A75B7CA3ED7F7@[192.168.1.44]> In-Reply-To: <696A0DF1-020B-48CB-BF38-6605EAD5BF1E@wanderview.com> References: <772532900-1257123963-cardhu_decombobulator_blackberry.rim.net-1402739480-@bda715.bisx.prod.on.blackberry> <4AEEBD4B.1050407@quip.cz> <5275583A0E66749DA096A22F@[192.168.1.44]> <696A0DF1-020B-48CB-BF38-6605EAD5BF1E@wanderview.com> X-Mailer: Mulberry/4.0.8 (Win32) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Virus-Scanned: clamav-milter 0.95.2 at juggler X-Virus-Status: Clean Subject: Re: Performance issues with 8.0 ZFS and sendfile/lighttpd 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, 06 Nov 2009 21:11:53 -0000 --On Friday, November 06, 2009 3:31 PM -0500 Ben Kelly wrote: > Have you tried adjusting vfs.zfs.arc_meta_limit? I've noticed the > default value for this is set poorly when the overall ARC size is small. > This happens because various structure's not actually allocated from the > ARC like dnodes and dbufs are included in the metadata usage stats. When > the ARC is large this is somewhat negligible, but for small ARCs it > overwhelms the calculated default metadata limit and you end up not > caching any real file system metadata. > > You could try increasing the metadata limit or even better increase your > maximum ARC size to something over 1GB. (I seem to remember your ARC > size is 128M from earlier in the thread). Nope, that was someone else, not setting any ARC limits (or any ZFS settings at all actually). > > Hope that helps. > > - Ben >