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 X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9305BCA9EC7 for ; Sat, 2 Nov 2019 14:03:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5FC5B2080F for ; Sat, 2 Nov 2019 14:03:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="TRgUnVcB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726440AbfKBODq (ORCPT ); Sat, 2 Nov 2019 10:03:46 -0400 Received: from mail-pg1-f193.google.com ([209.85.215.193]:45019 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726380AbfKBODq (ORCPT ); Sat, 2 Nov 2019 10:03:46 -0400 Received: by mail-pg1-f193.google.com with SMTP id e10so8218185pgd.11 for ; Sat, 02 Nov 2019 07:03:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=rtuDPqJZ0XL0I3niBJJ+k2E1GedQ1MMy4bRevHQ+bw4=; b=TRgUnVcByAkYuvAlQNyPJkaDxxox1KYzIF5hquLLmn0AzhQt8aFInkbMxUqlURVXiB 9QU50KrAmHGHmTDL2tmOXlQb86gQ8unGF489aAc1bnZiHQO++EHlyIys5M3tf0eQW9+S gg1W4vqdPvVdaWzmfeQ440jYVaDjpPXZg1yOKdsWpoEedXp/TNJt7FA5ldPmWon+k/XW AVtsx8+ydQQGGUia1foFd5z5v2GNXn1TjrQKrKvuG+IgqthJA0asa59G72PtTabQpuZS fkQZn/uW1mjGIFz/k+Lkvy3z1+ZXGXUEjy7troJE0PnxRbIL4ZUCFFIhPwkvQGiYkQEy CaCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=rtuDPqJZ0XL0I3niBJJ+k2E1GedQ1MMy4bRevHQ+bw4=; b=Fei0BJibHXy0NUmdbEWaruk6Z1Jw8IWInrsq0X11U9+p30yD958X6P3WcTRZ4j4rD8 b4VtAcRqYHr9nP8id3OYrRNGmuY4VxcoxlZ9/Sd02sEGmW+HtPw6yjxiPagFXbGH/uqb XGIqTpMP173/sArqQrPChBTumeDgVp/TyV0ghczU/UdrHI2+1w1ofVTrPleLe/KJcLbn E1Ilua7fH28L0+dSrp1KnT9M0sEGdGKKMf0NL11Yin28GAsrkxEZzsCmbvY+lTEE80RW J8WwTXMtwqlaiV1tgnij1ZvW9ESF8G4tiGXnsTruZcB29ApmTDeHCby4zdrdnV8PORKR FRgA== X-Gm-Message-State: APjAAAUs7a3WyPFv5D3K5haPXUuN+DFx182uF+qKXe9gUK4mmtUbsBns 2d/twoyZZf5PmjwvflLEXSOvew== X-Google-Smtp-Source: APXvYqzAGyaSRBGFZuWmHK1zrMVvhmAYfeg6v+AAzMTYsYhCLLu7ILJkm2DMFJVLiC4rb8ZjP2u+9g== X-Received: by 2002:a65:6290:: with SMTP id f16mr20439011pgv.40.1572703425334; Sat, 02 Nov 2019 07:03:45 -0700 (PDT) Received: from [192.168.1.188] ([66.219.217.79]) by smtp.gmail.com with ESMTPSA id x20sm9174065pfa.186.2019.11.02.07.03.43 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 02 Nov 2019 07:03:44 -0700 (PDT) Subject: Re: [PATCH V4] block: optimize for small block size IO To: Ming Lei Cc: linux-block@vger.kernel.org, Coly Li , Christoph Hellwig , Keith Busch , linux-bcache@vger.kernel.org References: <20191102072911.24817-1-ming.lei@redhat.com> From: Jens Axboe Message-ID: <606b9117-1fb6-780b-8fb1-001c06768a2e@kernel.dk> Date: Sat, 2 Nov 2019 08:03:42 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <20191102072911.24817-1-ming.lei@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 11/2/19 1:29 AM, Ming Lei wrote: > __blk_queue_split() may be a bit heavy for small block size(such as > 512B, or 4KB) IO, so introduce one flag to decide if this bio includes > multiple page. And only consider to try splitting this bio in case > that the multiple page flag is set. > > ~3% - 5% IOPS improvement can be observed on io_uring test over > null_blk(MQ), and the io_uring test code is from fio/t/io_uring.c > > bch_bio_map() should be the only one which doesn't use bio_add_page(), > so force to mark bio built via bch_bio_map() as MULTI_PAGE. > > RAID5 has similar usage too, however the bio is really single-page bio, > so not necessary to handle it. Thanks Ming, applied. -- Jens Axboe