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 9BF5AECAAD8 for ; Fri, 23 Sep 2022 15:19:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231282AbiIWPTY (ORCPT ); Fri, 23 Sep 2022 11:19:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59534 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229724AbiIWPTV (ORCPT ); Fri, 23 Sep 2022 11:19:21 -0400 Received: from mail-io1-xd2d.google.com (mail-io1-xd2d.google.com [IPv6:2607:f8b0:4864:20::d2d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4089C13746A for ; Fri, 23 Sep 2022 08:19:20 -0700 (PDT) Received: by mail-io1-xd2d.google.com with SMTP id p202so166923iod.6 for ; Fri, 23 Sep 2022 08:19:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date; bh=nBzYZNxiqwS8B8wtF4j5G6kTvhawC1R2E1pDH0ol8Ww=; b=3AqQfBjqICcqKiJzARi6Ht6xdhsQCR/4z6U3qHkqScv6uM+HA45gS2X8NBuWb3jgWz UD8Bgz1t4OyYKJkV3589UzKLmx/DgimVWPSEye6926Q6Qp8Vk1YQmNe82cINdpFnNtJB 0VFuIs8p0OTxciJLSxRnQirk4BlMvqu2yCzPDFrXFfOMGRs5Vo+Ojwz/IS34FfH4a7BB koppDnm7VDGJoSC23AO6M0g5efy8ksMb1JoU8svDAx/JBIApYJd/PxR20rjk33p7xfaU xNTOplNxnzppTFfF3SHwtwm9j7du6/52Fj9zB4BpVwCqKI6JX55fYi1xHNvWUE/KHU3n oFmA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date; bh=nBzYZNxiqwS8B8wtF4j5G6kTvhawC1R2E1pDH0ol8Ww=; b=B22Xd8F5Vh7rB8nRjTE9a/EEfYLGVfKzQ4t0CCGJjm4FVZ5IFXptsh98hQnuuWNsLg Oq3CrX0USRoshw3NowbLQJXqjD28bouaIuQDS7/f2OmAxlb0sB5fKT1qZYR9aWu/dmhm RRNkPxjji3rInuBsKcoENEuxLDsbj2w2aDyyvhBt/TfPBbOMoT7E+S0Qg2t3pbbnKmGz /RyYjWnLdjvA3OlXeRLKCHFqX9+bSx9aVwkyjErgtlAKFLSW0G7PVDw9F7IL8E9J9V5x Kcrc5tzjfBen4NoEUSVF5iUIFHsQC4KsUwcDMRE215CL+5Fi83sfYgHRe09ZYhihy2uK brXg== X-Gm-Message-State: ACrzQf2tGBlsk4lTQ2lFsL75tdiIIBeZKPFoO0yXhhQp78h7swoxIGDP iYhNF9CoPqqCUffeVVun5W7c+w== X-Google-Smtp-Source: AMsMyM5Tai736JME3Hle0FFNp1nDrUfTShe7bOnunKGGouTOODQqiIsYwkfT8nwAo0WOQGmx1dFrFg== X-Received: by 2002:a05:6638:43:b0:359:543e:a7d6 with SMTP id a3-20020a056638004300b00359543ea7d6mr4886375jap.166.1663946359509; Fri, 23 Sep 2022 08:19:19 -0700 (PDT) Received: from [192.168.1.94] ([207.135.234.126]) by smtp.gmail.com with ESMTPSA id j188-20020a0263c5000000b0035b0d6f3219sm3376200jac.75.2022.09.23.08.19.18 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 23 Sep 2022 08:19:19 -0700 (PDT) Message-ID: <6f7600be-d4b9-aeac-7dd1-71992a4dd5e8@kernel.dk> Date: Fri, 23 Sep 2022 09:19:15 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:102.0) Gecko/20100101 Thunderbird/102.2.2 Subject: Re: [PATCHSET 0/5] Enable alloc caching and batched freeing for passthrough Content-Language: en-US To: Christoph Hellwig Cc: linux-block@vger.kernel.org, linux-scsi@vger.kernel.org, linux-nvme@lists.infradead.org References: <20220922182805.96173-1-axboe@kernel.dk> From: Jens Axboe In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On 9/23/22 9:16 AM, Christoph Hellwig wrote: > On Thu, Sep 22, 2022 at 12:28:00PM -0600, Jens Axboe wrote: >> This is good for a 10% improvement for passthrough performance. For >> a non-drive limited test case, passthrough IO is now more efficient >> than the regular bdev O_DIRECT path. > > How so? If it ends up faster we are doing something wrong in the > normal path as there should be no fundamental difference in the work > that is being done. There's no fundamental difference, but the bdev path is more involved than the simple passthrough path. -- Jens Axboe