Return-Path: Received: from mail-iw0-f174.google.com ([209.85.214.174]:61844 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751060Ab1FJDHA (ORCPT ); Thu, 9 Jun 2011 23:07:00 -0400 Received: by iwn34 with SMTP id 34so1850869iwn.19 for ; Thu, 09 Jun 2011 20:07:00 -0700 (PDT) Message-ID: <4DF139D0.1080200@tonian.com> Date: Thu, 09 Jun 2011 14:23:28 -0700 From: Benny Halevy To: Jim Rees CC: Peng Tao , linux-nfs@vger.kernel.org, peter honeyman Subject: Re: [PATCH 87/88] Add configurable prefetch size for layoutget References: <09142112ff0115f7f22124a69ead7b9bb5e0958f.1307464382.git.rees@umich.edu> <4DEED80A.4000102@panasas.com> <20110608021852.GA20998@merit.edu> <4DF062D6.7010304@panasas.com> <20110609114929.GA28157@merit.edu> <4DF0CB5D.60000@panasas.com> <20110609135846.GA32565@merit.edu> In-Reply-To: <20110609135846.GA32565@merit.edu> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On 2011-06-09 06:58, Jim Rees wrote: > Benny Halevy wrote: > > > My understanding is that layoutget specifies a min and max, and the server > > There's a min. What do you consider the max? > Whatever gets into csa_fore_chan_attrs.ca_maxresponsesize? > > The spec doesn't say max, it says "desired." I guess I assumed the server > wouldn't normally return more than desired. No, the server may freely upgrade the returned layout segment by returning a layout for a larger byte range or even returning a RW layout where a READ layout was asked for. Benny > > 18.43.3. DESCRIPTION > ... > > The LAYOUTGET operation returns layout information for the specified > byte-range: a layout. The client actually specifies two ranges, both > starting at the offset in the loga_offset field. The first range is > between loga_offset and loga_offset + loga_length - 1 inclusive. > This range indicates the desired range the client wants the layout to > cover. The second range is between loga_offset and loga_offset + > loga_minlength - 1 inclusive. This range indicates the required > range the client needs the layout to cover. Thus, loga_minlength > MUST be less than or equal to loga_length. > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html