From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752719Ab1KIGYq (ORCPT ); Wed, 9 Nov 2011 01:24:46 -0500 Received: from mail-wy0-f174.google.com ([74.125.82.174]:60473 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751074Ab1KIGYp (ORCPT ); Wed, 9 Nov 2011 01:24:45 -0500 Message-ID: <1320819875.26025.48.camel@edumazet-laptop> Subject: Re: Large file copy to NFS mounted directory causes delay in other application packets From: Eric Dumazet To: Manavalan Krishnan Cc: "linux-kernel@vger.kernel.org" , netdev Date: Wed, 09 Nov 2011 07:24:35 +0100 In-Reply-To: <1320816503.73813.YahooMailNeo@web160718.mail.bf1.yahoo.com> References: <1320816503.73813.YahooMailNeo@web160718.mail.bf1.yahoo.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.0- Content-Transfer-Encoding: 8bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le mardi 08 novembre 2011 à 21:28 -0800, Manavalan Krishnan a écrit : > Hi All > > I have two systems with two network interfaces each(eth0 and eth1). I > am running linux-HA (heartbeat deamon) on both the systems and they > use eth0 for exchanging heartbeats. I have NFS mounted directory in > one system and the NFS client uses the interface eth1. > > I try to copy a large file to NFS mounted directory. But the heartbeat > daemons misses the heartbeat packets from peers while copy is under > progress. I did tcpdump and found that the heartbeat packets are > delayed for few seconds before sent out on eth0. When I stop the file > copy, the heartbeats are delivered properly. It seems linux kernel > somehow giving priority for NFS packets(generated from the file copy) > over other application packets. > > Any thoughts on this behavior? Is there any way we can avoid this so > that application packets get equal chance while large file copy to NFS > mounted directory under progress? > CC netdev 1) Is your NFS using UDP or TCP ? 2) Is your eth0 dedicated to heartbeats and eth1 to NFS traffic ? 3) How do you know heartbeats are delayed ? 4) Is your server CPU bounded ? Thanks