From: Trond Myklebust Subject: Re: [PATCH] Smooth out NFS client writeback Date: Thu, 02 Jun 2005 00:38:30 -0400 Message-ID: <1117687110.10822.114.camel@lade.trondhjem.org> References: <20050602032609.47381.qmail@web30715.mail.mud.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain Cc: nfs@lists.sourceforge.net Return-path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.11] helo=sc8-sf-mx1.sourceforge.net) by sc8-sf-list2.sourceforge.net with esmtp (Exim 4.30) id 1DdhTp-0004Da-NN for nfs@lists.sourceforge.net; Wed, 01 Jun 2005 21:38:53 -0700 Received: from pat.uio.no ([129.240.130.16] ident=7411) by sc8-sf-mx1.sourceforge.net with esmtp (TLSv1:AES256-SHA:256) (Exim 4.41) id 1DdhTn-0003nr-Pi for nfs@lists.sourceforge.net; Wed, 01 Jun 2005 21:38:53 -0700 To: Shantanu Goel In-Reply-To: <20050602032609.47381.qmail@web30715.mail.mud.yahoo.com> Sender: nfs-admin@lists.sourceforge.net Errors-To: nfs-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: Discussion of NFS under Linux development, interoperability, and testing. List-Post: List-Help: List-Subscribe: , List-Archive: on den 01.06.2005 Klokka 20:26 (-0700) skreiv Shantanu Goel: > Here are some numbers with iozone (avg of 3 runs). > The command was run as: iozone -i0 -r4k -s64m -c -t4 > I manually booted the client machine with mem=256M. What happens when you increase the file size to significantly beyond the memory size on a slow network. That is the interesting case. Try, for instance, booting with mem=32m and iozone -s > I also ran iozone in mmap mode with same options as > above but specifying -B as well. The machine hung > with the stock client so could not complete the test. > Here are the numbers with the patched client. Where was the machine hanging? Cheers, Trond BTW: how did you determine the values for NFS_WRITE_CLUSTER and NFS_COMMIT_CLUSTER. they appear to be completely arbitrary AFAICS. Also, have you compared to the latest NFS_ALL kernels? They contain a bunch of extra latency fixes that came from Ingo's RT work. Finally, please explain _why_ have you removed the FLUSH_STABLE from nfs_writepage()? The reason for it in the existing code is to avoid the extra COMMIT call in situations where we know we are already very low on memory. I don't see anything new in your patches that avoids these low memory situations. ------------------------------------------------------- This SF.Net email is sponsored by Yahoo. Introducing Yahoo! Search Developer Network - Create apps using Yahoo! Search APIs Find out how you can build Yahoo! directly into your own Applications - visit http://developer.yahoo.net/?fr=offad-ysdn-ostg-q22005 _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs