Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 4 Apr 2001 14:29:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 4 Apr 2001 14:29:28 -0400 Received: from mail.ureach.com ([63.150.151.36]:7944 "EHLO ureach.com") by vger.kernel.org with ESMTP id ; Wed, 4 Apr 2001 14:29:14 -0400 Date: Wed, 4 Apr 2001 14:28:33 -0400 Message-Id: <200104041828.OAA22823@www21.ureach.com> To: linux-kernel@vger.kernel.org From: Kapish K Reply-to: Subject: nfs performance at high loads Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-vsuite-type: e Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hello, We have been seeing some problems with running nfs benchmarks at very high loads and were wondering if somebody could show some pointers to where the problem lies. The system is a 2.4.0 kernel on a 6.2 Red at distribution ( so nfs utils from 6.2 and the nfsd of 2.4.0 ) - the benchmark run is the SPECsfs97 benchmarks that runs through a series of the nfs operations. We have about 4 nfs clients, each invoking the operations via 8 processes. Everything goes fine till the 500-1000 IOPs mark - no errors, response time is good (0.8 sec/op )and throughput is as expected. But at the 1500 IOPs mark, errors show up ( nfs operations failure ) and response time drops to 1.4 Msec/Op. Continue to 2000 IOPs, there is a drop in the error count and the response time improves to 1.0 Msec/Op. But from there on, it gets worse, at 2500 IOPs and 3000 IOPs with huge number of nfs errors and finally the nfs server console scrolls on with an endless number of 'alloc-pages: 0-order allocation failed' and the clients shutdown due to too many rpc call failures and all that can be done on the server is to reboot the system as it becomes practically locked for all purposes. Any hints or directions to follow or as to whether such a benchmark testing has been carried out by somebody else for nfs performance would be very much appreciated. Thanks, KK ________________________________________________ Get your own "800" number Voicemail, fax, email, and a lot more http://www.ureach.com/reg/tag - 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/