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=-4.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,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 E4CD7C07E96 for ; Thu, 8 Jul 2021 06:05:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C1BE261CE6 for ; Thu, 8 Jul 2021 06:05:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229763AbhGHGIf (ORCPT ); Thu, 8 Jul 2021 02:08:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49804 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229608AbhGHGIe (ORCPT ); Thu, 8 Jul 2021 02:08:34 -0400 Received: from mail-pg1-x52a.google.com (mail-pg1-x52a.google.com [IPv6:2607:f8b0:4864:20::52a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CAEF5C061574 for ; Wed, 7 Jul 2021 23:05:52 -0700 (PDT) Received: by mail-pg1-x52a.google.com with SMTP id t9so4858454pgn.4 for ; Wed, 07 Jul 2021 23:05:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=x42eN8t1nMi/Qglwv0rlMAjFJm2O+TOdrEms1zHn4NQ=; b=tOGLoDCjJytRKdTKXzCyYio9r+dpnqrIzljrH/SEZ6NBACxwh+dBkb8lum4raL+Byb 4iYCphC41sEg9DKDi9bmeClMjkuwL7EUtBd5g40XG0ROiz6tOgnq86m907rBIlqeB9R4 QKXNR7gbJFI6cbQcrsJ5yrTBPKZYckKE9Tb9DaCIrXYbHnKtpFkGJBghidhlDWZ6Xx6x IOi6TOJMrz5amgLuUKmMNn4IULO04xxd7xRS82Htl1kTEhBB8pou3xybuzwQhBCxpI95 1rfNN1IB1xVzz8RvKfz72TOsOn8carJtzyVv+LHG0CXxiAsX4yF/8JPKskgqYUX6n654 Hikw== 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=x42eN8t1nMi/Qglwv0rlMAjFJm2O+TOdrEms1zHn4NQ=; b=Q1fbVvZMRphd5e6rFgpantGU7cpAeAW0602sAJzqcpGdyO8nM491UVZITeoTAR2l/y QGCe1K8byJ06nNNAJK0KsVtfV+oEkn350hKfCmI0IlD01sK5Sb/bWa0kKNo/mRh/NRub 4YGbJHQuNsntZxExOzU8HosCvCvB296Z9Lh/ssirayFeL2TumwWhzj9ZeRxuIxy/vQyX TLRBD/iS+5El65FIg5ijIGue3hKEvGY0oYDEIi26JP0gIuH3eAe5w8HWHj9M3UkfplF5 MrWJg/JhIAtyqbPdRq1PiWAwSi5COcJRxeKCxSCkGjPX9i2Sb3ylX6sZlIlB470km1Op vGOg== X-Gm-Message-State: AOAM532bGOSyf2gTULwt3RsrP2d/m1lzA78iqfJN9dixZRhOvGN0RNpB J6QK3o/Hji90SWOH1XZgMJoRu2YKnrc= X-Google-Smtp-Source: ABdhPJxAY/FpP2nc+9GkK5Hnw1a5db47aHRayb7swtKRyTTDHzdoBKcMgmfXzeV/kaJcF3wEmTaaag== X-Received: by 2002:a05:6a00:168a:b029:2fb:6bb0:aba with SMTP id k10-20020a056a00168ab02902fb6bb00abamr30009557pfc.32.1625724352361; Wed, 07 Jul 2021 23:05:52 -0700 (PDT) Received: from jianchwadeMacBook-Pro.local ([154.48.252.69]) by smtp.gmail.com with ESMTPSA id 198sm367989pfw.21.2021.07.07.23.05.50 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 07 Jul 2021 23:05:52 -0700 (PDT) Subject: Re: Discard performance regression after "scsi: sd: Remove LBPRZ dependency for discards" To: "Martin K. Petersen" Cc: jejb@linux.ibm.com, linux-scsi@vger.kernel.org References: <279cb008-4c92-0535-efdd-6e877bea7349@gmail.com> From: Wang Jianchao Message-ID: Date: Thu, 8 Jul 2021 14:05:49 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Thanks so much for your comment, Martin ;) That's really helpful. Jianchao On 2021/7/8 11:23 AM, Martin K. Petersen wrote: > > Wang, > >> We have a sata ssd with following parameters, >> >> max_ws_blocks = 0 >> max_unmap_blocks = 262143 >> lbprz = 1 >> lbpu = 1 >> unmap_limit_for_ws = 0 > > The device is explicitly asking for us to use UNMAP so the older kernel > choosing WRITE SAME(16) was not correct. > > I have been working on an update to the discard/zeroing heuristics that > I'll post when 5.15 opens next week. But based on what's reported it by > your device we would still choose UNMAP for discards. LBPRZ only affects > which command we use for zeroing. >