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 38FEBC433F5 for ; Fri, 18 Mar 2022 14:43:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237396AbiCROoz (ORCPT ); Fri, 18 Mar 2022 10:44:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53886 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237382AbiCROoy (ORCPT ); Fri, 18 Mar 2022 10:44:54 -0400 Received: from mail-wr1-x42d.google.com (mail-wr1-x42d.google.com [IPv6:2a00:1450:4864:20::42d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3DCF32E5768 for ; Fri, 18 Mar 2022 07:43:35 -0700 (PDT) Received: by mail-wr1-x42d.google.com with SMTP id h23so11422702wrb.8 for ; Fri, 18 Mar 2022 07:43:35 -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 :cc:references:from:in-reply-to:content-transfer-encoding; bh=b5IgM1pfmqfbVyXrPizgzoTapsKtV7N1PmRvPG0bDn8=; b=U9Wr1Q4bESQeoe2fX5d51zV8zODH27hcQ+yET7A+AnsvZCryl/GIaJPgikhyQfdnAV Ss8EokDC7SYlIBbKNiLzedKtNqyRs8mL88hSzb3bz3INpQKzxoyKlx1j16tRpE2cIO43 FKuNcUSJuK6h7pKLTzJWj7zE8W88sWHIt40u+3vqOhMWUXYI5hvjf+Jx/aH8Xm+OLlsJ dDUdpbXeGwsr/Q3cUKq1ipvlXm0fNU/HbdRpuEnOnKpKUr7DX4PXpMjYI30wrVg4VkLj FBhE6pKTowYW0T6zEu4bUzRpT29ZDBQPIeDh1b6rW3Any8CHJ826vRJ9+GBetT2X5QjE SKwQ== 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=b5IgM1pfmqfbVyXrPizgzoTapsKtV7N1PmRvPG0bDn8=; b=ZfTCZ1wgzdRhTtjqPZMV9Iu7Ph9Bz/wngV9uTtcG/IgZia60ktZEyMrLswArnOkV4D 85KE6TfDJosme2gYAxpXprHIW+lYTqgHJqrGcm3C16aXLIN2tdiBsiZty9FPfO8mgrgt R+u2i9jcwtXB1bHRrluDYuAqL4mOZbXmzpzG/2WWZnBsWCm6zJnvXrAfWy7wwbP+qZm8 mmtNL8UxTqzIuMcfhb7KZPPLBp/jB1am9bYUlM0PXoLkrsoDBkvDx35ow/MX2CAzd2lw ls6X1LunNJ3tXaMtnlXMw1a7XecySfZtgIn8AxBtMtzbpouQsZLu3wJA57BNdo/OeeZd +P3g== X-Gm-Message-State: AOAM533OeSTUeihrql1TC+rkZLS3mZRack0goN9fAMkJWTuMyA8ixB6M F+hNBWCZTrPKQkYzFgnsOUOGraNp7gMUYw== X-Google-Smtp-Source: ABdhPJxG77nuEo2kX6IyDo9vkNvnMCDfcJD+nT96nyz+jl+Brn6xpmiLnY8VgVFu1LZ/oTZpJuddNQ== X-Received: by 2002:a5d:4b84:0:b0:203:e89d:71a1 with SMTP id b4-20020a5d4b84000000b00203e89d71a1mr7066146wrt.274.1647614613596; Fri, 18 Mar 2022 07:43:33 -0700 (PDT) Received: from [192.168.8.198] ([85.255.234.70]) by smtp.gmail.com with ESMTPSA id m64-20020a1c2643000000b0038c85aade4csm2590662wmm.11.2022.03.18.07.43.33 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 18 Mar 2022 07:43:33 -0700 (PDT) Message-ID: <016bd177-1621-c6c1-80a2-adfabe929d2f@gmail.com> Date: Fri, 18 Mar 2022 14:42:10 +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: io-uring@vger.kernel.org Cc: Jens Axboe References: 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 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. Also, want to play after to see if we can also avoid taking uring_lock. > Pavel Begunkov (4): > io_uring: get rid of raw fill cqe in kill_timeout > io_uring: get rid of raw fill_cqe in io_fail_links > io_uring: remove raw fill_cqe from linked timeout > io_uring: optimise compl locking for non-shared rings > > fs/io_uring.c | 126 ++++++++++++++++++++++------------ > include/uapi/linux/io_uring.h | 1 + > 2 files changed, 85 insertions(+), 42 deletions(-) > -- Pavel Begunkov