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 5ADCEC433F5 for ; Mon, 27 Dec 2021 05:49:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235248AbhL0FtU convert rfc822-to-8bit (ORCPT ); Mon, 27 Dec 2021 00:49:20 -0500 Received: from mailgate.zerties.org ([144.76.28.47]:43096 "EHLO mailgate.zerties.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230061AbhL0FtU (ORCPT ); Mon, 27 Dec 2021 00:49:20 -0500 Received: from p4fc6d4a2.dip0.t-ipconnect.de ([79.198.212.162] helo=localhost) by mailgate.zerties.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1n1ism-000Abu-KU; Mon, 27 Dec 2021 05:49:17 +0000 From: Christian Dietrich To: Hao Xu , Jens Axboe Cc: io-uring@vger.kernel.org, Joseph Qi , horst.schirmeier@tu-dresden.de, "Franz-B. Tuneke" , Hendrik Sieck In-Reply-To: <78dbcb47-edde-2d44-a095-e53469634926@linux.alibaba.com> Organization: Technische =?utf-8?Q?Universit=C3=A4t?= Hamburg References: <20211214055734.61702-1-haoxu@linux.alibaba.com> <78dbcb47-edde-2d44-a095-e53469634926@linux.alibaba.com> X-Commit-Hash-org: f01fca33b1535359a4f3d7fe903261c35a059bba X-Commit-Hash-Maildir: ac664cc432896bf059ddccae881df3aa66f23cf4 Date: Mon, 27 Dec 2021 06:49:11 +0100 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT X-SA-Do-Not-Rej: Yes X-SA-Exim-Connect-IP: 79.198.212.162 X-SA-Exim-Mail-From: stettberger@dokucode.de Subject: Re: [POC RFC 0/3] support graph like dependent sqes Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Hao Xu [27. Dezember 2021]: > Hi Christian, > Great! Thanks for the testing, a question here: the first generator > iouring means BPF-enhanced iouring? No, actually not. I've only shown the plain io_uring vs. linear systemcall here. Within the generator, I call the io_uring+bpf just 'bpf'. > I currently don't have a specifuc use case, just feel this may be useful > since there are simple cases like open-->parallel reads->close that > linear dependency doesn't apply, so this POC is sent more like to get > people's thought about user cases.. That is in principle a good idea. However, as Franz can tell you, for many uses cases predefining the followup actions does not work. For example, for reads, it can happen that you get a short read, whereby you cannot directly continue to the next action. chris -- Prof. Dr.-Ing. Christian Dietrich Operating System Group (E-EXK4) Technische Universität Hamburg Am Schwarzenberg-Campus 3 (E), 4.092 21073 Hamburg eMail: christian.dietrich@tuhh.de Tel: +49 40 42878 2188 WWW: https://osg.tuhh.de/