From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Latchesar Ionkov" Subject: Re: Re: NFSv4/pNFS possible POSIX I/O API standards Date: Wed, 6 Dec 2006 18:25:42 -0500 Message-ID: References: <6.2.3.4.2.20061127213243.04f786c0@cic-mail.lanl.gov> <20061128055428.GA29891@infradead.org> <20061129090450.GA16296@infradead.org> <20061129122313.GG14315@parisc-linux.org> <20061129123913.GA15994@infradead.org> <4570ACD1.7060800@mcs.anl.gov> <4574BF52.6090600@mcs.anl.gov> <4575E83F.8090501@mcs.anl.gov> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "Christoph Hellwig" , "Matthew Wilcox" , "Gary Grider" , linux-fsdevel@vger.kernel.org Return-path: Received: from nf-out-0910.google.com ([64.233.182.186]:56960 "EHLO nf-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S937786AbWLFXZo (ORCPT ); Wed, 6 Dec 2006 18:25:44 -0500 Received: by nf-out-0910.google.com with SMTP id o25so702401nfa for ; Wed, 06 Dec 2006 15:25:43 -0800 (PST) To: "Rob Ross" In-Reply-To: <4575E83F.8090501@mcs.anl.gov> Content-Disposition: inline Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On 12/5/06, Rob Ross wrote: > I unfortunately don't have data to show exactly where the time was > spent, but it's a good guess that it is all the network traffic in the > open() case. Is it hard to repeat the test and check what requests (and how much time do they take) PVFS server receives? > Well you've caught me. I don't want to cache the values, because I > fundamentally believe that sharing state between clients and servers is > braindead (to use Christoph's phrase) in systems of this scale > (thousands to tens of thousands of clients). So I don't want locks, so I > can't keep the cache consistent, ... Having file handles in the server looks like a cache to me :) What are the properties of a cache that it lacks? Thanks, Lucho