From: Trond Myklebust Subject: Re: Read/Write NFS I/O performance degraded by FLUSH_STABLE page flushing Date: Fri, 29 May 2009 19:13:09 -0400 Message-ID: <1243638789.7155.194.camel@heimdal.trondhjem.org> References: <41044976-395B-4ED0-BBA1-153FD76BDA53@oracle.com> <1243618968.7155.60.camel@heimdal.trondhjem.org> <1243620455.7155.80.camel@heimdal.trondhjem.org> <1243621769.7155.97.camel@heimdal.trondhjem.org> <1243628519.7155.150.camel@heimdal.trondhjem.org> Mime-Version: 1.0 Content-Type: text/plain Cc: Chuck Lever , linux-nfs@vger.kernel.org, linux-nfs-owner@vger.kernel.org, Peter Staubach To: Brian R Cowan Return-path: Received: from mail-out2.uio.no ([129.240.10.58]:38504 "EHLO mail-out2.uio.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751756AbZE2XNP (ORCPT ); Fri, 29 May 2009 19:13:15 -0400 In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org List-ID: On Fri, 2009-05-29 at 19:02 -0400, Brian R Cowan wrote: > If you can explain how pulling that ONE change can cause the performance > issue to essentially disappear, I'd be more than happy to *try* to get a > 2.6.30 test environment configured. Getting ClearCase to *install* on > kernel.org kernels is a non-trivial operation, requiring modifications to > install scripts, module makefiles, etc. Then there is the issue of > verifying that nothing else is impacted, all before I can begin to do this > test. We're talking days here. > > To be blunt, I'd need something I can take to a manager who will ask me > why I'm spending so much time on an issue when we "already have the > cause." It's simple: you are the one asking for a change to the established kernel behaviour, so you get to justify that change. Saying "it breaks clearcase on RHEL-5" is not a justification, and I won't accept to ack the change. Trond