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 671EDC433F5 for ; Fri, 18 Mar 2022 15:36:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232955AbiCRPhl (ORCPT ); Fri, 18 Mar 2022 11:37:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236141AbiCRPhk (ORCPT ); Fri, 18 Mar 2022 11:37:40 -0400 Received: from mail-wr1-x436.google.com (mail-wr1-x436.google.com [IPv6:2a00:1450:4864:20::436]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8672770CC1 for ; Fri, 18 Mar 2022 08:36:21 -0700 (PDT) Received: by mail-wr1-x436.google.com with SMTP id j18so2618074wrd.6 for ; Fri, 18 Mar 2022 08:36:21 -0700 (PDT) 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:to :references:from:in-reply-to:content-transfer-encoding; bh=R40yylOn/eaKkKKf1ZOuRbCnSNvwPSXt9wYzkZBasTY=; b=F9mfMheFXmIvMF1A7qPTdmBtJ6ibzXhrbKHuzBUaHpFHje+r9hWbDrQmMVRpI34dIJ CORAZhb86hCLB+bIqDiuP8lnTcb5IrapN+Mr3A+M2+j5oWAAr2NrbpHpB6aCNLqf8I/V 4+VgYBmz9vIMC2Q1aOdMNkxZ6xcTF8+VRPnLOaeOAiJprmZPgD+NlOE+J5B3NIHNSx8e lnXQ5hiftQrZjfiS+FPcXufFQNerY3pjPPGe/R0nfXv7kmyaJjsj1rDay8gDnnXKZfaz U0Wg/6f2EHDVjsu09G9Tsdbo+zLLp1WO4uXUl9E8bQDb9WpYwrDDCuSNevTumMsp/bkO F8hA== 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:references:from:in-reply-to :content-transfer-encoding; bh=R40yylOn/eaKkKKf1ZOuRbCnSNvwPSXt9wYzkZBasTY=; b=gJL8VdR0ngSw+PvFD6qBZb2W+Gxf/CgZaGMVYBJRBNNIUUDuKYCV4JOPUptEOBr82V iYHYYRak7u89mPM3C0cL8VCNPYmotDcMT9epPHLSu61VQu/92L77xiOH9peTb8WfXIVx xPCKYooxWPbjHPvCa9Q79QY1FC8LTY82MCEEAt91TLsGtnW1E4mBUNtcnrYhM+9N7Jnq knsY7BYRdU1dKhYxdzQ947RA4lhg+CIMI8xrRl/j6eRSgUn2jPDUFDvVIUQ9cLQ6jroK XNXKb7furp0o8WbhXh00zNqkb/umG+N2dDoORIplKwGY85IxfRlIrlD6vNegq6pGjZIB 0U3A== X-Gm-Message-State: AOAM533TPXP0M+MAcI5InXGOsehfOBX2jUA/zYFlgtUC0nKQnNgJ3pPb 5v94PgpgF7ZW7v3r70yAhYRHyfTINmOXEg== X-Google-Smtp-Source: ABdhPJzEqY+ggrwZ85CBBqJf9IAVA5zO48WgcyNkcl+bhgOMhjud5J9oLoo3UXB9ra8x8YH9rzvGYA== X-Received: by 2002:adf:90e2:0:b0:1e3:f5a:553c with SMTP id i89-20020adf90e2000000b001e30f5a553cmr8182649wri.476.1647617780102; Fri, 18 Mar 2022 08:36:20 -0700 (PDT) Received: from [192.168.8.198] ([85.255.234.70]) by smtp.gmail.com with ESMTPSA id x3-20020a5d6b43000000b001e317fb86ecsm6757877wrw.57.2022.03.18.08.36.19 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 18 Mar 2022 08:36:19 -0700 (PDT) Message-ID: Date: Fri, 18 Mar 2022 15:34:52 +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: [RFC 0/4] completion locking optimisation feature Content-Language: en-US To: Jens Axboe , io-uring@vger.kernel.org References: <016bd177-1621-c6c1-80a2-adfabe929d2f@gmail.com> <23c1e47b-45e5-242f-a563-d257a7de88ed@kernel.dk> <458031c4-2eca-7a9e-ab9f-183a2497af48@gmail.com> From: Pavel Begunkov In-Reply-To: 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 3/18/22 15:22, Jens Axboe wrote: > On 3/18/22 9:00 AM, Pavel Begunkov wrote: >> On 3/18/22 14:52, Jens Axboe wrote: >>> On 3/18/22 8:42 AM, Pavel Begunkov wrote: >>>> On 3/18/22 13:52, Pavel Begunkov wrote: >>>>> A WIP feature optimising out CQEs posting spinlocking for some use cases. >>>>> For a more detailed description see 4/4. >>>>> >>>>> Quick benchmarking with fio/t/io_uring nops gives extra 4% to throughput for >>>>> QD=1, and ~+2.5% for QD=4. >>>> >>>> Non-io_uring overhead (syscalls + userspace) takes ~60% of all execution >>>> time, so the percentage should quite depend on the CPU and the kernel config. >>>> Likely to be more than 4% for a faster setup. >>>> >>>> fwiw, was also usingIORING_ENTER_REGISTERED_RING, if it's not yet included >>>> in the upstream version of the tool. >>> >>> But that seems to be exclusive of using PRIVATE_CQ? >> >> No, it's not. Let me ask to clarify the description and so, why do you >> think it is exclusive? > > Didn't dig too deep, just saw various EINVAL around registered files and > updating/insertion. And the fact that t/io_uring gets -EINVAL on Ah, those are for registered rsrc with tags, just because they use fill_cqe, need to do something about them > register with op 20 (ring fd) if I set CQ_PRIVATE, see other email. -- Pavel Begunkov