From owner-freebsd-questions@FreeBSD.ORG Wed Dec 31 08:04:28 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 362C11065677 for ; Wed, 31 Dec 2008 08:04:28 +0000 (UTC) (envelope-from peter@boosten.org) Received: from smtpq1.tb.mail.iss.as9143.net (smtpq1.tb.mail.iss.as9143.net [212.54.42.164]) by mx1.freebsd.org (Postfix) with ESMTP id B64768FC1B for ; Wed, 31 Dec 2008 08:04:27 +0000 (UTC) (envelope-from peter@boosten.org) Received: from [212.54.42.133] (helo=smtp2.tb.mail.iss.as9143.net) by smtpq1.tb.mail.iss.as9143.net with esmtp (Exim 4.69) (envelope-from ) id 1LHw42-0002x9-9l; Wed, 31 Dec 2008 09:04:26 +0100 Received: from [84.25.72.219] (helo=ra.egypt.nl) by smtp2.tb.mail.iss.as9143.net with esmtp (Exim 4.69) (envelope-from ) id 1LHw40-0007Ld-JH; Wed, 31 Dec 2008 09:04:24 +0100 Received: from [192.168.13.81] (iPod.egypt.nl [192.168.13.81]) by ra.egypt.nl (Postfix) with ESMTP id 3FD1A3989E; Wed, 31 Dec 2008 09:04:19 +0100 (CET) References: <20081216094719.EDCEE1065675@hub.freebsd.org> <495930E4.1030501@dugas-family.org> <20081229230115.F68805@wojtek.tensor.gdynia.pl> <4959DFEF.5090407@dugas-family.org> <20081230150507.U87347@wojtek.tensor.gdynia.pl> <495A3957.9050002@dugas-family.org> <495A3C72.5070802@unsane.co.uk> <20081230201351.L12391@wojtek.tensor.gdynia.pl> <495A9595.6080201@dugas-family.org> <20081231002557.D45571@wojtek.tensor.gdynia.pl> <495B2516.4020904@dugas-family.org> Message-Id: From: Peter Boosten To: Bernard Dugas In-Reply-To: <495B2516.4020904@dugas-family.org> Content-Type: text/plain; charset=us-ascii; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit X-Mailer: iPod Mail (5G77) Mime-Version: 1.0 (iPod Mail 5G77) Date: Wed, 31 Dec 2008 09:06:26 +0100 X-ZiggoSMTP-MailScanner-Information: Please contact the ISP for more information X-ZiggoSMTP-MailScanner-ID: 1LHw40-0007Ld-JH X-ZiggoSMTP-MailScanner: Found to be clean X-ZiggoSMTP-MailScanner-SpamCheck: not spam, SpamAssassin (not cached, score=0.687, required 5, BAYES_50 0.00, SPF_NEUTRAL 0.69) X-ZiggoSMTP-MailScanner-From: peter@boosten.org X-Spam-Status: No Cc: Wojciech Puchar , "freebsd-questions@freebsd.org" , Vincent Hoffman Subject: Re: Optimising NFS for system files X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 31 Dec 2008 08:04:28 -0000 On 31 dec 2008, at 08:53, Bernard Dugas wrote: > Wojciech Puchar wrote: > >>> nfsserver# time tar -cf - clientusr-amd64 > /dev/null >>> 5.001u 12.147s 1:23.92 20.4% 69+1369k 163345+0io 0pf+0w >>> >>> client9# time tar -cf - /usr > /dev/null >>> tar: Removing leading '/' from member names >>> 3.985u 19.779s 4:32.47 8.7% 74+1457k 0+0io 0pf+0w >>> >>> Note : clientusr-amd64 is around 1.3GB and is the same directory >>> exported to client9 /usr with nfs. >>> >> it's FAST. what's wrong? > > First thing that may be wrong is the understanding of the time > figures. The documentation is not clear about them and the -h option > is not working : > > client6# time -h tar -cf - /usr > /dev/null > -h: Command not found. > 0.000u 0.000s 0:00.00 0.0% 0+0k 0+0io 0pf+0w > > The main thing is that the 3rd figures 1:23.92 and 4:32.47 seems to > be the time i wait in front of the computer while it works (ok, i > know, i should enjoy a beer, or hot coffee with this nice snow ;-) : > > client9# date ; time tar -cf - /usr > /dev/null ; date ; > Wed Dec 31 08:23:59 CET 2008 > tar: Removing leading '/' from member names > 4.103u 19.651s 4:25.80 8.9% 74+1453k 0+0io 2pf+0w > Wed Dec 31 08:28:25 CET 2008 > > and 08:28:25 - 08:23:59 = 00:04:26 is very close to 4:25.80. > > On server, it means : 1440MB / 84s = 17MB/s > On client, that becomes : 1440MB / 266s = 5.4MB/s > > I know the disk is not very fast, but i would like the NFS layer not > to add too much... > > I don't want my users to wait between 3 or 4 times more because > computer is using NFS. In my opinion there are more considerations than only nfs: the data is pulled twice over the network, and the tar process might initiate paging which is done over the network as well. The tar comparison is not a good one. Peter -- http://www.boosten.org