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 504FDC05024 for ; Wed, 20 Sep 2023 20:46:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229658AbjITUqu (ORCPT ); Wed, 20 Sep 2023 16:46:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59336 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229473AbjITUqt (ORCPT ); Wed, 20 Sep 2023 16:46:49 -0400 Received: from mail-pl1-f174.google.com (mail-pl1-f174.google.com [209.85.214.174]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C63FB9; Wed, 20 Sep 2023 13:46:44 -0700 (PDT) Received: by mail-pl1-f174.google.com with SMTP id d9443c01a7336-1c43b4b02c1so1583885ad.3; Wed, 20 Sep 2023 13:46:44 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695242803; x=1695847603; 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:message-id:reply-to; bh=ykhgKtsX2cSkN4uX6LBnSBcD5nrfp6+TARNRJQaJR6c=; b=KjEpjqii7J5F+11Ktejpqmb7mKb4ne0/2TejTMZ7m/dSQvpsVcdq+vnCQ5CVBufidd M2un6GCezYGVACW2Q/dibpQBbIiBqSaib3FkIDoGfbE4Fi9E1qEky3UAYw/HkwfCg2IB 5IOxbChJv23D9p2l73NGbF0/JcDpSADag1taCyX7a4C0s6pN7NX0USp65Hsj5GIcik1h eb43ZrJ7cHcmJGVEoIK9wv+0f024I5daJXUH8LvlMQ8cPVfWAwCeCWIyTTBUuD1XutLl pyBvep6fxVSYHjMlGIx7NPHkWpz99YVYgn4oyKhwzVLkvWrgwBORdA25rfDRN+IKRbtk 8WGw== X-Gm-Message-State: AOJu0YxibkDPLXk3A9GMm8VH+98ZmyEix1W0YZe8TAY18pmkmWeCAgEA LbEb00aavWBKSgCK21USirQ= X-Google-Smtp-Source: AGHT+IHguTQYMss6/IXnNgOwpT4FcjQGDCqbCZ3melCWZ4OqXn8ID/L0Al/3KiqNr+xc0NSK5TDqPg== X-Received: by 2002:a17:902:7d87:b0:1c4:29dd:2519 with SMTP id a7-20020a1709027d8700b001c429dd2519mr2830020plm.67.1695242803527; Wed, 20 Sep 2023 13:46:43 -0700 (PDT) Received: from ?IPV6:2620:15c:211:201:b0c6:e5b6:49ef:e0bd? ([2620:15c:211:201:b0c6:e5b6:49ef:e0bd]) by smtp.gmail.com with ESMTPSA id z16-20020a170903019000b001ab2b4105ddsm12240212plg.60.2023.09.20.13.46.42 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 20 Sep 2023 13:46:42 -0700 (PDT) Message-ID: <1522d8ec-6b15-45d5-b6d9-517337e2c8cf@acm.org> Date: Wed, 20 Sep 2023 13:46:41 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 00/13] Pass data temperature information to zoned UFS devices Content-Language: en-US To: Matthew Wilcox Cc: Jens Axboe , linux-block@vger.kernel.org, linux-scsi@vger.kernel.org, linux-fsdevel@vger.kernel.org, "Martin K . Petersen" , Christoph Hellwig References: <20230920191442.3701673-1-bvanassche@acm.org> From: Bart Van Assche In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 9/20/23 12:28, Matthew Wilcox wrote: > On Wed, Sep 20, 2023 at 12:14:25PM -0700, Bart Van Assche wrote: >> Zoned UFS vendors need the data temperature information. Hence >> this patch series that restores write hint information in F2FS and >> in the block layer. The SCSI disk (sd) driver is modified such that >> it passes write hint information to SCSI devices via the GROUP >> NUMBER field. > > "Need" in what sense? Can you quantify what improvements we might > see from this patchset? Hi Matthew, This is what Jens wrote about 1.5 years ago in reply to complaints about the removal of write hint support making it impossible to pass write hint information to SSD devices: "If at some point there's a desire to actually try and upstream this support, then we'll be happy to review that patchset." (https://lore.kernel.org/linux-block/ef77ef36-df95-8658-ff54-7d8046f5d0e7@kernel.dk/). Hence this patch series. Recently T10 standardized how data temperature information should be passed to SCSI devices. One of the patches in this series translates write hint information into a data temperature for SCSI devices. This can be used by SCSI SSD devices (including UFS devices) to reduce write amplification inside the device because host software should assign the same data temperature to all data that will be garbage collected at once. Thanks, Bart.