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=-5.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 8D085C433ED for ; Thu, 29 Apr 2021 07:14:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4612F61449 for ; Thu, 29 Apr 2021 07:14:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232317AbhD2HP2 (ORCPT ); Thu, 29 Apr 2021 03:15:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57052 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237423AbhD2HP1 (ORCPT ); Thu, 29 Apr 2021 03:15:27 -0400 Received: from mail-ej1-x62a.google.com (mail-ej1-x62a.google.com [IPv6:2a00:1450:4864:20::62a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3D12CC06138B for ; Thu, 29 Apr 2021 00:14:41 -0700 (PDT) Received: by mail-ej1-x62a.google.com with SMTP id l4so98285544ejc.10 for ; Thu, 29 Apr 2021 00:14:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ionos.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=AqAWH45jRWdgyTy2vjfyUi3E8yZmGvelI1ZJKsPMIds=; b=VSwv9YS9I/lBFs/IN7IUEF+2BTCx3OHcMdiplR+lrXBXAtH2x6YeZiFSKtQfGwCJ63 chd7KsyX2OTqULmCqT+/JFtFbRRrtyG33bQM+KulrM4MKnQbBRFl74mgZbw59yWUAPez DFqO6aMuXnrQKTnv26qw5aFTMpK3U+Sl1DkDHkUOjhhoRt/fJnRKzPX4wWGJQtrmby6m safy4FK+iIbP3T7E8KdYhZWdLKpxzbiAl4rHB9Ba4ukvLRN1aMriWshXX1IetiOyuSoa 7xrmRhAUFYgnQegX08jGoZI+S9hdc+F/guYTR+Oue3DaZMRO4ZWqw4GENJsoigSEFzLQ 4etg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=AqAWH45jRWdgyTy2vjfyUi3E8yZmGvelI1ZJKsPMIds=; b=Ee1WffPsmRjtHlNjwmJNieOalcJ1dkcDcSGAnuoGU5k8HhCnYm3hfhL71AuqE5L7I8 qsUNsnOn9b27Tnd1oCbyIU3BISk+M9SE90ejSBK/ODT1qcrDbOABHKC77q81eGdm0bAB dNjKEIjBXSUdFP1ZytEIxswUyI9IHI5QnslKmsmQGUSj4XeTSAMESsnhTxqYDMkPxOPe hP8+m9pnfXb9oTv2v7EcvEhgbnHphZ0EgmNqrDJEN+HMTkNLK51a9GcdVxfPfj+O19CE fyuER7n1sN+kqjhTE0lhVYYVDtfSgzT8AQebM+L0Eqp+HPsUrBWu+KtXDGyQn5CY24EP OKOQ== X-Gm-Message-State: AOAM5339bEm9WySgdV+MAAMiYudT2C0zu+MrjTIHI5vubszP0ZCHlxFa ohQrih1MP+3R3vF3YZl9EDC9zw2G0G+VunQSmCxFcA== X-Google-Smtp-Source: ABdhPJyDNuaDth9n4XTzWoPlDtmpTv6KRYHjL6/OTOpzC+KOSr0mJjOzSMdo763CEyHtrUiP+KnAqXVqcYQd+aKtMew= X-Received: by 2002:a17:906:828b:: with SMTP id h11mr25061172ejx.305.1619680479976; Thu, 29 Apr 2021 00:14:39 -0700 (PDT) MIME-Version: 1.0 References: <20210428061359.206794-1-gi-oh.kim@ionos.com> <20210428061359.206794-5-gi-oh.kim@ionos.com> In-Reply-To: From: Gioh Kim Date: Thu, 29 Apr 2021 09:14:04 +0200 Message-ID: Subject: Re: [PATCH for-next 4/4] block/rnbd: Remove all likely and unlikely To: Chaitanya Kulkarni Cc: "linux-block@vger.kernel.org" , "axboe@kernel.dk" , "hch@infradead.org" , "sagi@grimberg.me" , "bvanassche@acm.org" , "haris.iqbal@ionos.com" , "jinpu.wang@ionos.com" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Wed, Apr 28, 2021 at 8:33 PM Chaitanya Kulkarni wrote: > > On 4/27/21 23:14, Gioh Kim wrote: > > The IO performance test with fio after removing the likely and > > unlikely macros in all if-statement shows no performance drop. > > They do not help for the performance of rnbd. > > > > The fio test did random read on 32 rnbd devices and 64 processes. > > Test environment: > > - AMD Opteron(tm) Processor 6386 SE > > - 125G memory > > - kernel version: 5.4.86 > > why 5.4 and not linux-block/for-next ? We have done porting only 5.4 for the server machine yet. > > > - gcc version: gcc (Debian 8.3.0-6) 8.3.0 > > - Infiniband controller: InfiniBand: Mellanox Technologies MT26428 > > [ConnectX VPI PCIe 2.0 5GT/s - IB QDR / 10GigE] (rev b0) > > > > before > > read: IOPS=549k, BW=2146MiB/s > > read: IOPS=544k, BW=2125MiB/s > > read: IOPS=553k, BW=2158MiB/s > > read: IOPS=535k, BW=2089MiB/s > > read: IOPS=543k, BW=2122MiB/s > > read: IOPS=552k, BW=2154MiB/s > > average: IOPS=546k, BW=2132MiB/s > > > > after > > read: IOPS=556k, BW=2172MiB/s > > read: IOPS=561k, BW=2191MiB/s > > read: IOPS=552k, BW=2156MiB/s > > read: IOPS=551k, BW=2154MiB/s > > read: IOPS=562k, BW=2194MiB/s > > ----------- > > average: IOPS=556k, BW=2173MiB/s > > > > The IOPS and bandwidth got better slightly after removing > > likely/unlikely. (IOPS= +1.8% BW= +1.9%) But we cannot make sure > > that removing the likely/unlikely help the performance because it > > depends on various situations. We only make sure that removing the > > likely/unlikely does not drop the performance. > > Did you get a chance to collect perf numbers to see which functions are > getting faster ? I knew somebody would ask for it ;-) No, I didn't because I have been occupied with another task. But I will check it soon in a few weeks. Thank you for the review. > >