Return-Path: linux-nfs-owner@vger.kernel.org Received: from smtp.mail.umich.edu ([141.211.12.86]:33656 "EHLO tombraider.mr.itd.umich.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750956Ab2BHUbp (ORCPT ); Wed, 8 Feb 2012 15:31:45 -0500 Date: Wed, 8 Feb 2012 15:31:40 -0500 From: Jim Rees To: "J. Bruce Fields" Cc: "Myklebust, Trond" , "linux-nfs@vger.kernel.org" Subject: Re: [RFC PATCH 1/2] NFSv4.1: Convert slotid from u8 to u32 Message-ID: <20120208203140.GA29238@umich.edu> References: <1328576237-7362-1-git-send-email-Trond.Myklebust@netapp.com> <20120208162322.GA13315@fieldses.org> <1328722042.3234.13.camel@lade.trondhjem.org> <20120208174901.GA28564@umich.edu> <20120208183151.GA14316@fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20120208183151.GA14316@fieldses.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: J. Bruce Fields wrote: On Wed, Feb 08, 2012 at 12:49:01PM -0500, Jim Rees wrote: > Myklebust, Trond wrote: > > 10GigE + high latencies is exactly where we're seeing the value. Andy > has been working with the high energy physics community doing NFS > traffic between the US and CERN... > > CITI to CERN is just over 120ms. I don't know what it would be from Andy's > house. Does he have 10G at home yet? That still seems short of what you'd need to get a 255MB bandwidth-delay product. I'm just curious what the experiment is here and whether there's a possibility the real problem is elsewhere. In my opinion, any fix that involves allocating multiple parallel data streams (rpc slots, tcp connections) is masking the real problem. But it's an effective fix.