From: Jeff Garzik Subject: Re: read-ahead in NFS server Date: Wed, 26 Dec 2007 21:34:23 -0500 Message-ID: <47730F2F.3080900@garzik.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Cc: linux-kernel@vger.kernel.org, NFS list To: saeed bishara Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:54521 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751824AbXL0Ce3 (ORCPT ); Wed, 26 Dec 2007 21:34:29 -0500 In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org List-ID: saeed bishara wrote: > Hi, > my NFS server seems not to utilize the read-ahead feature, my exported > dir is located on ext3 fs over sata disk. the sata controller can > issue commands up to 1MB, also I modified the read ahead under the sys > to 1MB. but when the client do reads in 32KB chunks (rsize), I can see > in the server side that all IOs are ~32KB. my kernel version is > 2.6.22.7. > according to the nfsd code, the NFS server should utilize the > read-ahead feature, but what should I do > to make it work? (linux-nfs added to cc) I cannot speak for the NFS server code specifically, but 32kb sounds like a network read (or write) data size limit. Are you using TCP? Are you using NFSv4, or an older version? Jeff