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 3C0A4ECAAA1 for ; Fri, 16 Sep 2022 20:01:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229932AbiIPUBX (ORCPT ); Fri, 16 Sep 2022 16:01:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56714 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230171AbiIPUBO (ORCPT ); Fri, 16 Sep 2022 16:01:14 -0400 Received: from mail-pf1-f171.google.com (mail-pf1-f171.google.com [209.85.210.171]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 338CE85AA3; Fri, 16 Sep 2022 13:01:13 -0700 (PDT) Received: by mail-pf1-f171.google.com with SMTP id d82so22214916pfd.10; Fri, 16 Sep 2022 13:01:13 -0700 (PDT) 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=aI55elBM47AbpRIfEoRwcS12RWAxkruf3PuVmLaNsIw=; b=F93+3ZCuhoW4ubfMQpiKJx3jYO2YUlD99AS4TKVJFHr2cITbQE1c4KZZRs/b07IsrF 71vE+0oKcC+g33vygMudbCM9cwLfEffrCHL8/A/+L/clX/M+Y9qZPw4M/qjDFlIgXdu4 QiO4Re/9Ms2VZfqmDL+rR2Vc0KfXNS97qFssyM8LltJkjy0UzXrAgw7IfaoaWtutTmPU i42jQJyTI0fiwaWDcW6yNDeBQ7uzf4Q7b4FmBsIt3OmzSMNf0HxsoeQSuyI6hq4igsq5 qPNbUBmnVVZqo5KKMlr1eusMZHJQQlmIRO2tUv5DYbp0P95iFjeEvAADhNcuahj3X1zI PSFg== X-Gm-Message-State: ACrzQf38Z+mWYa2pf9O4zTOOmr4B3B0I5QexSTkZ0OfBjQqItPY8DDxb tshmutsszHKV1RTldP+BpHQ= X-Google-Smtp-Source: AMsMyM7BtRpoBGm+25ZIcjQ1eDg7usENuczHgm9wgE8Sus1sUlVcptKPjg/7yVuSQ/Mc/WEtnHJpcQ== X-Received: by 2002:a63:e452:0:b0:42c:60ce:8b78 with SMTP id i18-20020a63e452000000b0042c60ce8b78mr5917990pgk.453.1663358472565; Fri, 16 Sep 2022 13:01:12 -0700 (PDT) Received: from ?IPV6:2620:15c:211:201:e470:c0f8:8896:5368? ([2620:15c:211:201:e470:c0f8:8896:5368]) by smtp.gmail.com with ESMTPSA id n10-20020a170902d2ca00b00174c235e1fdsm15550309plc.199.2022.09.16.13.01.09 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 16 Sep 2022 13:01:11 -0700 (PDT) Message-ID: <0be0e378-1601-678c-247a-ba24d111b934@acm.org> Date: Fri, 16 Sep 2022 13:01:08 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.12.0 Subject: Re: [PATCH RFC 0/8] Introduce provisioning primitives for thinly provisioned storage Content-Language: en-US To: Sarthak Kukreti , Stefan Hajnoczi Cc: dm-devel@redhat.com, linux-block@vger.kernel.org, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, Jens Axboe , "Michael S . Tsirkin" , Jason Wang , Paolo Bonzini , Alasdair Kergon , Mike Snitzer , Theodore Ts'o , Andreas Dilger , Bart Van Assche , Daniil Lunev , Evan Green , Gwendal Grignou References: <20220915164826.1396245-1-sarthakkukreti@google.com> 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-ext4@vger.kernel.org On 9/16/22 11:48, Sarthak Kukreti wrote: > Yes. On ChromiumOS, we regularly deal with storage devices that don't > support WRITE_ZEROES or that need to have it disabled, via a quirk, > due to a bug in the vendor's implementation. Using WRITE_ZEROES for > allocation makes the allocation path quite slow for such devices (not > to mention the effect on storage lifetime), so having a separate > provisioning construct is very appealing. Even for devices that do > support an efficient WRITE_ZEROES implementation but don't support > logical provisioning per-se, I suppose that the allocation path might > be a bit faster (the device driver's request queue would report > 'max_provision_sectors'=0 and the request would be short circuited > there) although I haven't benchmarked the difference. Some background information about why ChromiumOS uses thin provisioning instead of a single filesystem across the entire storage device would be welcome. Although UFS devices support thin provisioning I am not aware of any use cases in Android that would benefit from UFS thin provisioning support. Thanks, Bart.