From owner-freebsd-fs@FreeBSD.ORG Fri Sep 2 16:54:04 2011 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id D2DBF106564A for ; Fri, 2 Sep 2011 16:54:04 +0000 (UTC) (envelope-from brodbd@uw.edu) Received: from mail-ew0-f54.google.com (mail-ew0-f54.google.com [209.85.215.54]) by mx1.freebsd.org (Postfix) with ESMTP id 72DC68FC0C for ; Fri, 2 Sep 2011 16:54:04 +0000 (UTC) Received: by ewy1 with SMTP id 1so1935806ewy.13 for ; Fri, 02 Sep 2011 09:54:03 -0700 (PDT) MIME-Version: 1.0 Received: by 10.213.17.140 with SMTP id s12mr492906eba.111.1314980973922; Fri, 02 Sep 2011 09:29:33 -0700 (PDT) Received: by 10.213.22.210 with HTTP; Fri, 2 Sep 2011 09:29:33 -0700 (PDT) Date: Fri, 2 Sep 2011 09:29:33 -0700 Message-ID: From: David Brodbeck To: freebsd-fs@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: ZFSv28+NFSv4 poor file creation performance, "sync=disabled" has no effect X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 02 Sep 2011 16:54:05 -0000 I originally posted this on FreeBSD-questions, but it was suggested that I bring it here. I'm testing FreeBSD 9.0-BETA with an eye toward eventually using FreeBSD 9.0 to replace some existing OpenSolaris 2008.11 installations. I've found NFS file creation performance (as measured by Bonnie++) is equally slow for both with default settings. However, on OpenSolaris I disable the ZIL to improve file creation performance. This tuning parameter was removed from FreeBSD 9.0; its replacement is supposed to be the per-filesystem flag "sync", but setting this flag seems to have no effect. I did recompile the FreeBSD kernel without debugging features before doing the tests, so I don't think this is a case of debugging code slowing things down. Here's the relevant data; these are all from bonnie++'s "sequential create" benchmark. The NFS client was RedHat Enterprise Linux 5.6. OpenSolaris 2008.11, default settings: 58/second OpenSolaris 2008.11, with "zil_disable=1": 1258/second FreeBSD 9.0-BETA, default settings: 107/second FreeBSD 9.0-BETA, with "sync=disabled": 106/second So it appears the "sync" ZFS parameter has no effect in FreeBSD. Has anyone else seen this? Is there a way to improve NFS file creation performance now that zil_disable has been removed? -- David Brodbeck System Administrator, Linguistics University of Washington