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 EA3BEC433F5 for ; Fri, 4 Mar 2022 02:40:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232858AbiCDCky (ORCPT ); Thu, 3 Mar 2022 21:40:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46386 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232738AbiCDCky (ORCPT ); Thu, 3 Mar 2022 21:40:54 -0500 Received: from mail-ej1-x62f.google.com (mail-ej1-x62f.google.com [IPv6:2a00:1450:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A83F4579F for ; Thu, 3 Mar 2022 18:40:07 -0800 (PST) Received: by mail-ej1-x62f.google.com with SMTP id dr20so14563932ejc.6 for ; Thu, 03 Mar 2022 18:40:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language :from:to:references:in-reply-to:content-transfer-encoding; bh=n+7hfJGHFK3tcklKMnhllQjek8ThgfflqXtYyBPdZ08=; b=R0cMmlmjetHFKvw8twXsxHlLYNlTNFoZfaF2eHEsZx0iY+ek8pGufbPZ95Njv0fSKi qPvKxDukjw6lnGl6uJF1Sy/JwSRx/HV23iLvT/BH/nQLRAJHi7wEl8w7eBHqftRgjNf9 KDTWgLo2nuRQ9cRWEwxzBxWtLguBVgORBuz6hDKmyCIiNgr7HiVMdu20nC6BNkabL58Z EhcxZbZ3pmVa3UMiessI4fNTGggoPxCN13uZszUKfW51ZCTYrBEF52MTVjiMcDnZnPaO m6dvDWWuuYtByyezInN9q03FBJrEmVexOQXvFzXkGIbMZxTnw+6yZ9B4StsqaVpeWO5x aW7w== 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:from:to:references:in-reply-to :content-transfer-encoding; bh=n+7hfJGHFK3tcklKMnhllQjek8ThgfflqXtYyBPdZ08=; b=y75BskXSD1vaMpK441tddjAhVCTCBVVzYNWjqy8DI6DhA1584zZf/8fHzI9CsbWGfi GHCCPUdsMpEIN7ccru4ovbSm85vuQTa3AMgoslib8UxCun6+8R2eM+2ukZV3PjQ9yXic RbPXc16ZOGxm+jTFLN+kU/l/RzIdzESWm2OJ2R+RVezuj6VrBnAG8D2Re17CcocIMiKO YrVyMSs8jH3DlwnP6xGKlIifhgawftFSs0LKMwACFlSgq2bNroUbPXZvRQi4nTrh848a ldawPlvvxayYMpnQHSMbiGlVpLafslDn+MRT/8eI40EghJQbHNBpGbWhj99oTP3usACD 0zRg== X-Gm-Message-State: AOAM532IHUJaGSZqNvJyaECcXraBl6fWX6w945vkrIogR5SJw4qgLOnQ 4NxAoqK/w3IDaZFTzNf/OA0= X-Google-Smtp-Source: ABdhPJxWHL3SLL8QdSeq8UYPLxHRAplFg7GiRJF8xoeKPDOjr0HudTi0NXJTUsE5zARiAC3prclxQg== X-Received: by 2002:a17:906:2ed1:b0:6b6:bb09:178c with SMTP id s17-20020a1709062ed100b006b6bb09178cmr29877302eji.382.1646361606096; Thu, 03 Mar 2022 18:40:06 -0800 (PST) Received: from [192.168.8.198] ([85.255.236.114]) by smtp.gmail.com with ESMTPSA id a21-20020a1709062b1500b006da814b08c6sm1251205ejg.94.2022.03.03.18.40.05 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 03 Mar 2022 18:40:05 -0800 (PST) Message-ID: Date: Fri, 4 Mar 2022 02:35:30 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.6.0 Subject: Re: [PATCH] io_uring: add io_uring_enter(2) fixed file support Content-Language: en-US From: Pavel Begunkov To: Jens Axboe , Xiaoguang Wang , io-uring@vger.kernel.org References: <20220303052811.31470-1-xiaoguang.wang@linux.alibaba.com> <4f197b0e-6066-b59e-aae0-2218e9c1b643@kernel.dk> <528ce414-c0fe-3318-483a-f51aa8a407b9@kernel.dk> <040e9262-4ebb-8505-5a14-6f399e40332c@kernel.dk> <951ea55c-b6a3-59e4-1011-4f46fae547b3@kernel.dk> <559685fd-c8aa-d2d4-d659-f4b0ffc840d4@gmail.com> <5a0f0fe0-e180-90fc-aa23-4e0faa9896bc@gmail.com> In-Reply-To: <5a0f0fe0-e180-90fc-aa23-4e0faa9896bc@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 3/4/22 02:28, Pavel Begunkov wrote: > On 3/4/22 02:18, Jens Axboe wrote: >> On 3/3/22 6:49 PM, Pavel Begunkov wrote: >>> On 3/3/22 16:31, Jens Axboe wrote: >>>> On 3/3/22 7:40 AM, Jens Axboe wrote: >>>>> On 3/3/22 7:36 AM, Jens Axboe wrote: >>>>>> The only potential oddity here is that the fd passed back is not a >>>>>> legitimate fd. io_uring does support poll(2) on its file descriptor, so >>>>>> that could cause some confusion even if I don't think anyone actually >>>>>> does poll(2) on io_uring. >>>>> > [...] >>>> which is about a 15% improvement, pretty massive... >>> >>> Is the bench single threaded (including io-wq)? Because if it >>> is, get/put shouldn't do any atomics and I don't see where the >>> result comes from. >> >> Yes, it has a main thread and IO threads. Which is not uncommon, most >> things are multithreaded these days... > > They definitely are, just was confused by the bench as I can't > recall t/io_uring having >1 threads for nops and/or direct bdev I/O fwiw, not trying to say it doesn't use threads -- Pavel Begunkov