Return-Path: linux-nfs-owner@vger.kernel.org Received: from smtp.mail.umich.edu ([141.211.12.86]:58250 "EHLO tombraider.mr.itd.umich.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752141Ab2B1PJc (ORCPT ); Tue, 28 Feb 2012 10:09:32 -0500 Date: Tue, 28 Feb 2012 10:09:23 -0500 From: Jim Rees To: Chuck Lever Cc: Jeff Layton , Harshula , Steve Dickson , NeilBrown , linux-nfs@vger.kernel.org Subject: Re: "Using NFS over UDP on high-speed links such as Gigabit can cause silent data corruption." Message-ID: <20120228150923.GA13432@umich.edu> References: <1330406521.9157.16.camel@serendib> <20120228065218.7e110936@tlielax.poochiereds.net> <20120228124646.GA2528@umich.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org List-ID: Chuck Lever wrote: As above, most other uses of UDP do not involve large packets. But I wonder if it is appropriate for us to suggest a change in the default setting. A minute is certainly too long. Just a guess, but 4 seconds seems appropriate to me. That's good enough for gigabit ethernet. Anyone running fragmented 10G networks gets what they deserve. Yes, you can have more than four seconds of data in flight at moderate speeds, but unless something is terribly wrong the fragments should come in very close together.