From owner-freebsd-questions Sun Feb 9 16:21: 4 2003 Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 04DB237B401 for ; Sun, 9 Feb 2003 16:21:03 -0800 (PST) Received: from mail.seekingfire.com (coyote.seekingfire.com [24.72.10.212]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5CD4443F3F for ; Sun, 9 Feb 2003 16:21:02 -0800 (PST) (envelope-from tillman@seekingfire.com) Received: from blues.seekingfire.prv (blues.seekingfire.prv [192.168.23.211]) by mail.seekingfire.com (Postfix) with ESMTP id D4ABA45 for ; Sun, 9 Feb 2003 18:21:01 -0600 (CST) Received: (from tillman@localhost) by blues.seekingfire.prv (8.11.6/8.11.6) id h1A0Mkd12941 for freebsd-questions@FreeBSD.ORG; Sun, 9 Feb 2003 18:22:46 -0600 Date: Sun, 9 Feb 2003 18:22:46 -0600 From: Tillman To: freebsd-questions@FreeBSD.ORG Subject: Re: speeding up NFS Message-ID: <20030209182246.D32740@seekingfire.com> References: <200302091717.42138.ajacoutot@lphp.org> <20030209192839.GH5356@dan.emsphone.com> <20030209174109.B32740@seekingfire.com> <20030209234825.GJ5356@dan.emsphone.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <20030209234825.GJ5356@dan.emsphone.com>; from dnelson@allantgroup.com on Sun, Feb 09, 2003 at 05:48:25PM -0600 X-Urban-Legend: There is lots of hidden information in headers Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Sun, Feb 09, 2003 at 05:48:25PM -0600, Dan Nelson wrote: > In the last episode (Feb 09), Tillman said: > > Which sysctl is this? The closest I can find is: > > > > # sysctl -a | grep nfs | grep sync > > vfs.nfs.async: 0 > > Same one. They split the server sysctls out into nfsrv in 5.*. That makes sense. > > If that's the one, it may still not be necessary. I'm getting about > > 8.5-9 Megabytes/s on NFS reads from a Linux 2.4 client (on a 100Mbit > > switched LAN) with it set to 0, as measured by Bonnie++. This is > > fairly close to the 12MB/s fast ethernet theoretical maximum, so I'm > > happy with performance. > > It only applies to writes. With it set to 0 (the default), FreeBSD > follows the NFS spec and does not return from NFSv2 write or NFSv3 > commit calls without having synced the data to disk. This can slow you > down if you are not on a battery-backed RAID or ramdisk. With NFSv3 > it's not so bad since it supports async client writes (i.e. separate > write and commit calls). When I was benchmarking with bonnie++, I found NFSv2 with async writes turned on to be only marginally faster than v3 with sync'ed commits (under 10% difference). Given the additional safety, I like using sync :-) Thanks for the info, -T -- A man may fight the greatest enemy, take the longest journey, survive the most grievous wound -- and still be helpless in the hands of the woman he loves. - Zensunni Wisdom from the Wandering To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message