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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 61410C43603 for ; Sun, 15 Dec 2019 12:20:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 25E0C2054F for ; Sun, 15 Dec 2019 12:20:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="rGuorTMc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726207AbfLOMU4 (ORCPT ); Sun, 15 Dec 2019 07:20:56 -0500 Received: from mail-ot1-f44.google.com ([209.85.210.44]:35542 "EHLO mail-ot1-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726099AbfLOMUz (ORCPT ); Sun, 15 Dec 2019 07:20:55 -0500 Received: by mail-ot1-f44.google.com with SMTP id o9so5254519ote.2 for ; Sun, 15 Dec 2019 04:20:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=I2IreTQ93dL5ePJ58xne5SlIrHlddgsBPfpXJi8+oag=; b=rGuorTMcyK1XCxKltons+4V3qgramX04z6SMcSEp03caMfgF2GzsFBqGYOZ8PkXvGo Q4Z0a+ae++wSi4WD3q5yeXTNvR5l1vZkADUkRW1M597bsLBbMlyJBV3oS8gmpY51KvgT eoXehYJNToOaOrxnH7mdFR2I8ekpehd5je6hDd7FYC3qQEQpPahe+MQJ8pez5cMLzBUl eTjL508SO05/s7thNfaQSZZ2F+maejq2c2H4sjp0bpNDZBP0qKj45+ONbeZjZW+z7ujv lpVADhJ6TTAJMY3RsMZ7TVR74rYm8ybbuj/LLsMg8eP3kn2ZYa3+nTgtDs3jyM4MBWlb sk3g== 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=I2IreTQ93dL5ePJ58xne5SlIrHlddgsBPfpXJi8+oag=; b=AySz4FcIry+tqMvjuILxv5sGWacBRIknN3gLrdtE4vLShlfdXKkYegbpZPECZSl4/S 0LxmB/Nl52njjtZn2ALMxzBibksIFLpwe85M4g/QixGFEpC1aXbSj5vyYkScrcnLdYuP 1s3FyDQaBkx3+TgF6Lb1t90guL9rRdKYWv+bdAleiCY0fUgxOvuZeR26AN7WKUzuLlAd ilgSeUb3/HOcne+JWjNoNHniJL43bXr75wRPVTkbWy9FGSEPLIT928iOumb6xJnOrQKZ rfwanN48oYrsXqR2C41GktKN94gZQWnc8OJVM+whFOjjNw/MjmoSCx9N9s4RI7LBQROT VylA== X-Gm-Message-State: APjAAAWx46gYIEZfTWOiW+RV550YSUOCCk6oBVt/CpqiEyfJjkc2j2vY AjFRIN2om7dAYKhqXDi1yN1EitX4duW5WY/NA0Y8AuxNDoQ= X-Google-Smtp-Source: APXvYqylFb959LXkQrJOwiCpd2QnaE8Qyp9siBQ2P3HYiC0zLhUlIfgp7KI25Np+vatOWixAaOsQtF42LUgY5LR6cyg= X-Received: by 2002:a9d:588c:: with SMTP id x12mr25245625otg.2.1576412454862; Sun, 15 Dec 2019 04:20:54 -0800 (PST) MIME-Version: 1.0 References: <2b0e5191-740f-0530-4825-0b0b6b653efb@gmx.com> In-Reply-To: <2b0e5191-740f-0530-4825-0b0b6b653efb@gmx.com> From: Jorge Bastos Date: Sun, 15 Dec 2019 12:20:44 +0000 Message-ID: Subject: Re: RAID5 scrub performance To: Qu Wenruo Cc: Btrfs BTRFS Content-Type: text/plain; charset="UTF-8" Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org One last data point on this from a larger pool, 11 disk raid5 pool (raid1 metadata), this is probably not a very recommended configuration but it's a 3rd backup and mostly for testing raid5 on a larger pool: UUID: 1236acc8-dbd5-41bd-bf3d-872a8fbbce49 Scrub started: Sun Dec 15 11:23:45 2019 Status: running Duration: 0:51:34 Time left: 90:06:52 ETA: Thu Dec 19 06:22:13 2019 Total to scrub: 18.10TiB Bytes scrubbed: 175.12GiB Rate: 57.96MiB/s Error summary: no errors found Same pool during a btrfs send to /dev/null: btrfs send /mnt/disks/Pics/T12_disk1_Pics_2019-12-15-0829/ | pv -bart > /dev/null At subvol /mnt/disks/Pics/T12_disk1_Pics_2019-12-15-0829/ 447GiB 0:13:19 [ 635MiB/s] [ 573MiB/s] ^ ^ cur. spd / avg. spd So looks to me like scrub performance is around 1/10 of what it should be, and not optimal to wait multiple days to scrub a larger pool. Jorge