From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752765Ab3B1LZc (ORCPT ); Thu, 28 Feb 2013 06:25:32 -0500 Received: from smtp.eu.citrix.com ([46.33.159.39]:46246 "EHLO SMTP.EU.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751223Ab3B1LZb (ORCPT ); Thu, 28 Feb 2013 06:25:31 -0500 X-IronPort-AV: E=Sophos;i="4.84,755,1355097600"; d="scan'208";a="2017938" Message-ID: <512F3EA9.1070704@citrix.com> Date: Thu, 28 Feb 2013 12:25:29 +0100 From: =?ISO-8859-1?Q?Roger_Pau_Monn=E9?= User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:17.0) Gecko/20130216 Thunderbird/17.0.3 MIME-Version: 1.0 To: Jan Beulich CC: "xen-devel@lists.xen.org" , "linux-kernel@vger.kernel.org" Subject: Re: [Xen-devel] [PATCH RFC 00/12] xen-block: indirect descriptors References: <1362047335-26402-1-git-send-email-roger.pau@citrix.com> <512F443702000078000C1DF7@nat28.tlf.novell.com> In-Reply-To: <512F443702000078000C1DF7@nat28.tlf.novell.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 28/02/13 11:49, Jan Beulich wrote: >>>> On 28.02.13 at 11:28, Roger Pau Monne wrote: >> This series contains the initial implementation of indirect >> descriptors for Linux blkback/blkfront. >> >> Patches 1, 2, 3, 4 and 5 are bug fixes and minor optimizations. >> >> Patch 6 contains a LRU implementation for blkback that will be needed >> when using indirect descriptors (since we are no longer able to map >> all possible grants blkfront might use). > > Considering this, ... > >> Patch 7 is an addition to the print stats function in blkback in order >> to print information regarding persistent grant usage. >> >> Patches 8, 9, 10 and 11 are preparatory work for indirect descriptors >> implementation, mainly make blkback use dynamic memory and remove the >> shared blkbk structure, so each blkback instance has it's own list of >> free requests, pages, handles and so on. >> >> Finally patch 12 contains the indirect descriptors implementation. >> >> I've also pushed this series to the following git repository: >> >> git://xenbits.xen.org/people/royger/linux.git xen-block-indirect >> >> Performance benefit of this series can be seen in the following graph: >> >> http://xenbits.xen.org/people/royger/plot_indirect.png > > ... would you happen to also have a comparison with using > indirect descriptors but not persistent grants? IOW I'm > wondering about the hit rate on the persistently mapped > grants, especially when blkfront really saturates the added > bandwidth. This is the expanded graph that also contains indirect descriptors without persistent grants: http://xenbits.xen.org/people/royger/plot_indirect_nopers.png