Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932891AbbLOB0s (ORCPT ); Mon, 14 Dec 2015 20:26:48 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:58415 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753647AbbLOB0q (ORCPT ); Mon, 14 Dec 2015 20:26:46 -0500 MIME-Version: 1.0 In-Reply-To: <566E9A7E.3030203@redhat.com> References: <1402680562-8328-1-git-send-email-ming.lei@canonical.com> <1402680562-8328-3-git-send-email-ming.lei@canonical.com> <53A06475.7000308@redhat.com> <53A06E05.9060708@redhat.com> <566E9A7E.3030203@redhat.com> Date: Tue, 15 Dec 2015 09:26:44 +0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [RFC PATCH 2/2] block: virtio-blk: support multi virt queues per virtio-blk device From: Ming Lei To: Paolo Bonzini Cc: Jens Axboe , "Michael S. Tsirkin" , linux-kernel , Linux Virtualization , Stefan Hajnoczi , linux-api@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1742 Lines: 43 Hi Paolo, On Mon, Dec 14, 2015 at 6:31 PM, Paolo Bonzini wrote: > > > On 18/06/2014 06:04, Ming Lei wrote: >> For virtio-blk, I don't think it is always better to take more queues, and >> we need to leverage below things in host side: >> >> - host storage top performance, generally it reaches that with more >> than 1 jobs with libaio(suppose it is N, so basically we can use N >> iothread per device in qemu to try to get top performance) >> >> - iothreads' loading(if iothreads are at full loading, increasing >> queues doesn't help at all) >> >> In my test, I only use the current per-dev iothread(x-dataplane) >> in qemu to handle 2 vqs' notification and precess all I/O from >> the 2 vqs, and looks it can improve IOPS by ~30%. >> >> For virtio-scsi, the current usage doesn't make full use of blk-mq's >> advantage too because only one vq is active at the same time, so I >> guess the multi vqs' benefit won't be very much and I'd like to post >> patches to support that first, then provide test data with >> more queues(8, 16). > > Hi Ming Lei, > > would you like to repost these patches now that MQ support is in the kernel? > > Also, I changed my mind about moving linux-aio to AioContext. I now > think it's a good idea, because it limits the number of io_getevents > syscalls. O:-) So I would be happy to review your patches for that as well. OK, I try to figure out a new version, and it might take a while since it is close to festival season, :-) Thanks, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/