From mboxrd@z Thu Jan 1 00:00:00 1970 From: "work-usenet@nouce.net" Subject: Questiong regarding change in support for > 256 outstanding read/write operations per mount point for linux clients Date: Wed, 09 Jun 2004 09:10:41 -0400 Sender: nfs-admin@lists.sourceforge.net Message-ID: <40C70C50.7030105@nouce.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Return-path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.12] helo=sc8-sf-mx2.sourceforge.net) by sc8-sf-list2.sourceforge.net with esmtp (Exim 4.30) id 1BY2qs-0000G7-By for nfs@lists.sourceforge.net; Wed, 09 Jun 2004 06:10:46 -0700 Received: from [208.234.30.51] (helo=aitcom.net) by sc8-sf-mx2.sourceforge.net with esmtp (Exim 4.30) id 1BY2qr-0000e8-KJ for nfs@lists.sourceforge.net; Wed, 09 Jun 2004 06:10:45 -0700 Received: from nouce.net (fay-gateway.aitcom.net [208.234.1.225]) by aitcom.net (8.12.10/8.12.10) with ESMTP id i59CsUmB011300 for ; Wed, 9 Jun 2004 08:54:31 -0400 To: nfs@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: *Is there a backpatch to allow this change in a 2.4 kernel and/or has this been added to the 2.6 client? As I use NFS on 2.4 based Linux systems. But would like to see if this client change would help performance problems I'm seeing with clients connecting to an Netapp filer. Thanks. B7. I have achieved pretty fast speeds in some client benchmarks, but when my client is heavily loaded, it slows down considerably. Why does that happen? * *A.* The Linux client limits the total number of pending read or write operations per mount point. This prevents the client from exhausting its memory with cached read or write requests when the network or server is slow. The hard limit is 256 outstanding read or write operations per mount point. When that limit is reached, the client does not issue a new read or write operation until at least one outstanding read or write operation completes, thus serializing all reads and writes on that mount point until load is reduced. Two ways of mitigating this effect are to: 1. Increase rsize and wsize on your client's mount points. This increases the amount of data that can be involved in outstanding reads or writes at any given time. 2. Mount the same server partition multiple times on your clients, and spread your applications among the mount points. This limit has been removed in the 2.5 NFS client (after 2.5.47). ------------------------------------------------------- This SF.Net email is sponsored by: GNOME Foundation Hackers Unite! GUADEC: The world's #1 Open Source Desktop Event. GNOME Users and Developers European Conference, 28-30th June in Norway http://2004/guadec.org _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs