From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on gnuweeb.org X-Spam-Level: X-Spam-Status: No, score=-0.0 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_PASS,SPF_SOFTFAIL autolearn=ham autolearn_force=no version=3.4.6 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD760C433EF for ; Sat, 30 Apr 2022 13:12:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238772AbiD3NPZ (ORCPT ); Sat, 30 Apr 2022 09:15:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229921AbiD3NPW (ORCPT ); Sat, 30 Apr 2022 09:15:22 -0400 Received: from mail-pl1-x62a.google.com (mail-pl1-x62a.google.com [IPv6:2607:f8b0:4864:20::62a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2506F6D96D for ; Sat, 30 Apr 2022 06:11:59 -0700 (PDT) Received: by mail-pl1-x62a.google.com with SMTP id c23so9326506plo.0 for ; Sat, 30 Apr 2022 06:11:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=rbHJXY572fQPlY1/oCQ8lTxni098FTYcSyKejnNxvz8=; b=QTpcQr+eFHJeVUB3NWSouQNbGpXHjM9CJjKwBm7FT8MWsvqUMWVojIpivPVnqoTYCQ zDZL07GjYyITVKinpFSM10/BXoZohACn6MV+DOUDtZbAEd9QUa6Xba07D0ph/AdN4SD7 IRTZYq00D94UF5XPHUW0WFFVLsTX3g6qX44Ttk6VVcumew5i7BI/SENp3ctGGlEp6V4E ItTW8HbtJjKuxWmk9FXXGDU8Py6aeL4qwgQf/AUy1CMDXmIwe6zAbg2deEKo3X/I6XWs Um/0quaYaPylB0pDXSPmrAOnQbwxWXQTBemm2D313Vm5u0B38BpitPSP77hhno1IgV1h 07rw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=rbHJXY572fQPlY1/oCQ8lTxni098FTYcSyKejnNxvz8=; b=TCDQjuP2HYtiK8qqFyjrzCZcvqhEKuYv3VDtj6dQC6K5tRT8XEzyHqHnB2bc4Q7Vg5 SfzBOGkDFUDK4qn2st97jGANPhEH9l8l7c95TKw4SEUGnXz0xr/IVubTpJZ7S8/V8g2E NHIZ+/dqJDPx8A5hF488v25b1qgU5HD8M+QPh7qLEMFsSzGPGGTj5hRlb4yIXRpYmxrN l4ris0oMJx0KyqLTUPr85h5t2Fv6GAB5VLFxTPwxbnWnviJnGBlBcedohB3hYUU5MAWz VEYinOlCOZobPSkIx/jte4XWo6Bn3vJKAd8An7VNsWUoKumSW2+S2zYCKhI4mHftEkCz HGnQ== X-Gm-Message-State: AOAM530F/txMoeY5kbd/oXwx7Fmgsq4Jh+RD2ac7U7urj7y0TddCP92m m3YVxG/pgv8ji36g8QVvXVa8Ny6PcBfmB90C X-Google-Smtp-Source: ABdhPJzVqX3K1GClAeYIsxafdj7jRZuQQtXP9i0vIO68TCqT5CfARItWrFP+FaVbjmsJi7Png8RPQw== X-Received: by 2002:a17:90a:7c04:b0:1d7:d7e6:2916 with SMTP id v4-20020a17090a7c0400b001d7d7e62916mr9059401pjf.25.1651324318443; Sat, 30 Apr 2022 06:11:58 -0700 (PDT) Received: from [192.168.1.100] ([198.8.77.157]) by smtp.gmail.com with ESMTPSA id mj19-20020a17090b369300b001d29a04d665sm16268718pjb.11.2022.04.30.06.11.57 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 30 Apr 2022 06:11:57 -0700 (PDT) Message-ID: Date: Sat, 30 Apr 2022 07:11:56 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Subject: Re: [RFC v3 0/9] fixed worker Content-Language: en-US To: Hao Xu , io-uring@vger.kernel.org Cc: Pavel Begunkov , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org References: <20220429101858.90282-1-haoxu.linux@gmail.com> From: Jens Axboe In-Reply-To: <20220429101858.90282-1-haoxu.linux@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 4/29/22 4:18 AM, Hao Xu wrote: > This is the third version of fixed worker implementation. > Wrote a nop test program to test it, 3 fixed-workers VS 3 normal workers. > normal workers: > ./run_nop_wqe.sh nop_wqe_normal 200000 100 3 1-3 > time spent: 10464397 usecs IOPS: 1911242 > time spent: 9610976 usecs IOPS: 2080954 > time spent: 9807361 usecs IOPS: 2039284 > > fixed workers: > ./run_nop_wqe.sh nop_wqe_fixed 200000 100 3 1-3 > time spent: 17314274 usecs IOPS: 1155116 > time spent: 17016942 usecs IOPS: 1175299 > time spent: 17908684 usecs IOPS: 1116776 I saw these numbers in v2 as well, and I have to admit I don't understand them. Because on the surface, it sure looks like the first set of results (labeled "normal") are better than the second "fixed" set. Am I reading them wrong, or did you transpose them? I think this patch series would benefit from a higher level description of what fixed workers mean in this context. How are they different from the existing workers, and why would it improve things. > things to be done: > - Still need some thinking about the work cancellation Can you expand? What are the challenges with fixed workers and cancelation? > - not very sure IO_WORKER_F_EXIT is safe enough on synchronization > - the iowq hash stuff is not compatible with fixed worker for now We might need to extract the hashing out a bit so it's not as tied to the existing implementation. -- Jens Axboe