From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10B80C77B7C for ; Sat, 6 May 2023 01:39:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232415AbjEFBjR (ORCPT ); Fri, 5 May 2023 21:39:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59302 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232505AbjEFBjO (ORCPT ); Fri, 5 May 2023 21:39:14 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A7938468F for ; Fri, 5 May 2023 18:38:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1683337112; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=mAqtXf2OpHZh/aPmso1gikHVJkWfhblGK7GUt1MWQkc=; b=EkzOCBmjXt/1kse/qop1nixHneF4n3QkAWgH7MirHS8mr9WcXZWD5TMNfRfYB3UdTvABRX p5dqMLtTxSgcfq8f1qChfi8V6zT8OIg8rosO5Z823LIJLaLO+gVJLrZ6vcnVJdyxD6opRX C+bsvD0Ua8yK08uLA0iY5gegoPwnvug= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-75-BPpM903FMwiyv21hONGl9A-1; Fri, 05 May 2023 21:38:29 -0400 X-MC-Unique: BPpM903FMwiyv21hONGl9A-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 3EBB3185A78B; Sat, 6 May 2023 01:38:29 +0000 (UTC) Received: from ovpn-8-16.pek2.redhat.com (ovpn-8-16.pek2.redhat.com [10.72.8.16]) by smtp.corp.redhat.com (Postfix) with ESMTPS id F0A63492B00; Sat, 6 May 2023 01:38:22 +0000 (UTC) Date: Sat, 6 May 2023 09:38:17 +0800 From: Ming Lei To: Bernd Schubert Cc: Jens Axboe , Pavel Begunkov , Miklos Szeredi , Christoph Hellwig , Ziyang Zhang , Xiaoguang Wang , "lsf-pc@lists.linux-foundation.org" , "io-uring@vger.kernel.org" , "linux-block@vger.kernel.org" Subject: Re: [LSF/MM/BPF TOPIC] ublk & io_uring: ublk zero copy support Message-ID: References: <41cfb9c2-9774-e9e1-d8e7-4999a710f2e7@ddn.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <41cfb9c2-9774-e9e1-d8e7-4999a710f2e7@ddn.com> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Fri, May 05, 2023 at 09:57:47PM +0000, Bernd Schubert wrote: > Hi Ming, > > On 4/29/23 04:18, Ming Lei wrote: > > Hello, > > > > ublk zero copy is observed to improve big chunk(64KB+) sequential IO performance a > > lot, such as, IOPS of ublk-loop over tmpfs is increased by 1~2X[1], Jens also observed > > that IOPS of ublk-qcow2 can be increased by ~1X[2]. Meantime it saves memory bandwidth. > > > > So this is one important performance improvement. > > > > So far there are three proposal: > > looks like there is no dedicated session. Could we still have a > discussion in a free slot, if possible? Sure, and we can invite Pavel to the talk too if he is in this lsfmm. thanks, Ming