Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757297AbYBUPRf (ORCPT ); Thu, 21 Feb 2008 10:17:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751970AbYBUPRZ (ORCPT ); Thu, 21 Feb 2008 10:17:25 -0500 Received: from ti-out-0910.google.com ([209.85.142.190]:24326 "EHLO ti-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751746AbYBUPRY (ORCPT ); Thu, 21 Feb 2008 10:17:24 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=EZ0WFFBRvgZoi2hfLwKY/t/esWqGOA5yzYWLuhSuz+03A66HBn1bbvv4HAz1TVsw/Vx9bjC7bCjHgDzoQWZiFFccjjUzHDL4FKI6/B4kIjpbV3FS5aQehQp6sxbvwV9dlLezir79tEafvH0iujENp3dmgU/bZnHcrUL/VaBxtEQ= Message-ID: <4d569c330802210717g48d60229t56dd31f9828bad88@mail.gmail.com> Date: Thu, 21 Feb 2008 10:17:19 -0500 From: "Kevin Coffman" To: "David Howells" Subject: Re: [PATCH 00/37] Permit filesystem local caching Cc: "Daniel Phillips" , Trond.Myklebust@netapp.com, nfsv4@linux-nfs.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@tycho.nsa.gov, casey@schaufler-ca.com In-Reply-To: <28196.1203605703@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080220160557.4715.66608.stgit@warthog.procyon.org.uk> <200802201907.40406.phillips@phunq.net> <28196.1203605703@redhat.com> X-Google-Sender-Auth: bf3832d065e9c41e Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1203 Lines: 30 On Thu, Feb 21, 2008 at 9:55 AM, David Howells wrote: > Daniel Phillips wrote: > > > > Have you got before/after benchmark results? > > See attached. > > These show a couple of things: > > (1) Dealing with lots of metadata slows things down a lot. Note the result of > looking and reading lots of small files with tar (the last result). The > NFS client has to both consult the NFS server *and* the cache. Not only > that, but any asynchronicity the cache may like to do is rendered > ineffective by the fact tar wants to do a read on a file pretty much > directly after opening it. > > (2) Getting metadata from the local disk fs is slower than pulling it across > an unshared gigabit ethernet from a server that already has it in memory. Hi David, Your results remind me of this in case you're interested... http://www.citi.umich.edu/techreports/reports/citi-tr-92-3.pdf -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/