From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fieldses.org ([173.255.197.46]:42282 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758040AbdCUTDl (ORCPT ); Tue, 21 Mar 2017 15:03:41 -0400 Date: Tue, 21 Mar 2017 15:03:39 -0400 From: "J. Bruce Fields" To: Olga Kornievskaia Cc: Christoph Hellwig , linux-fsdevel@vger.kernel.org, Linux NFS Mailing List , ng-linux-team Subject: Re: [PATCH v1 2/3] VFS permit cross device vfs_copy_file_range Message-ID: <20170321190339.GE17872@fieldses.org> References: <20170302160211.30451-1-kolga@netapp.com> <20170302160211.30451-3-kolga@netapp.com> <20170302160714.GA4760@lst.de> <0ADCDD29-61BA-46CA-902C-06A6F7D06450@netapp.com> <20170315180913.GB18135@fieldses.org> <20170321155000.GB15402@fieldses.org> <56CDE406-AE24-40E4-852C-1C47C5CCD37E@netapp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <56CDE406-AE24-40E4-852C-1C47C5CCD37E@netapp.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Tue, Mar 21, 2017 at 12:03:08PM -0400, Olga Kornievskaia wrote: > Thank you for the update. I guess I don’t see how the proposed NFS > implementation is complicated and ugly (but I’m biased). I’ll try to > give you some performance number. My 1 data point (1gb) inter copy > showed 30% improvement (how can that be ignored). That would be useful, thanks--if it comes with some details about the setup. I'm not so curious about percent improvement, as how to predict the performance on a given network. If server-to-server copy looks like it's normally able to use close to the available bandwidth between the two servers, and if a traditional read-write-copy loop is similarly able to use the available bandwidth, then I can figure out whether server-to-server copy will help on my setup. --b.