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=-2.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 060A1C432C0 for ; Thu, 21 Nov 2019 01:51:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B46232084D for ; Thu, 21 Nov 2019 01:51:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="f4zWxhkc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726038AbfKUBve (ORCPT ); Wed, 20 Nov 2019 20:51:34 -0500 Received: from mout.gmx.net ([212.227.17.20]:33477 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725854AbfKUBvd (ORCPT ); Wed, 20 Nov 2019 20:51:33 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1574301091; bh=HvgsuwLGKrhkFDxpHIy8SpBrR1IySnIjne/2GUX4gs8=; h=X-UI-Sender-Class:Subject:To:References:From:Date:In-Reply-To; b=f4zWxhkcCBArBDGQREJ34JeeTa9duC17vwfOj34cca3l9whleZfUW/v6R+2G4zcMB b7ejZCp/SHTfCYYyuhIxcKmk1H7R7A3bndTaXDW86BWSiZflnr6AdmcYMhbHbnsx4B uRInOnmHi6LWDPezi2UlaZZyoTaxt/wOmsTBzGvU= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [0.0.0.0] ([13.231.109.76]) by mail.gmx.com (mrgmx105 [212.227.17.174]) with ESMTPSA (Nemesis) id 1MpDJX-1i412T327T-00qmzZ; Thu, 21 Nov 2019 02:51:31 +0100 Subject: Re: freezes during snapshot creation/deletion -- to be expected? (Was: Re: btrfs based backup?) To: Christian Pernegger , linux-btrfs References: <20191112183425.GA1257@tik.uni-stuttgart.de> <7f628741-b32e-24dc-629f-97338fde3d16@googlemail.com> From: Qu Wenruo Autocrypt: addr=quwenruo.btrfs@gmx.com; prefer-encrypt=mutual; keydata= mQENBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAG0IlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT6JAU4EEwEIADgCGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1oQAKCRDC PZHzoSX+qCY6CACd+mWu3okGwRKXju6bou+7VkqCaHTdyXwWFTsr+/0ly5nUdDtT3yEVggPJ 3VP70wjlrxUjNjFb6iIvGYxiPOrop1NGwGYvQktgRhaIhALG6rPoSSAhGNjwGVRw0km0PlIN D29BTj/lYEk+jVM1YL0QLgAE1AI3krihg/lp/fQT53wLhR8YZIF8ETXbClQG1vJ0cllPuEEv efKxRyiTSjB+PsozSvYWhXsPeJ+KKjFen7ebE5reQTPFzSHctCdPnoR/4jSPlnTlnEvLeqcD ZTuKfQe1gWrPeevQzgCtgBF/WjIOeJs41klnYzC3DymuQlmFubss0jShLOW8eSOOWhLRuQEN BFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcgaCbPEwhLj 1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj/IrRUUka 68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fNGSsRb+pK EKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0q1eW4Jrv 0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEvABEBAAGJ ATwEGAEIACYCGwwWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1rgUJCWpOfwAKCRDCPZHz oSX+qFcEB/95cs8cM1OQdE/GgOfCGxwgckMeWyzOR7bkAWW0lDVp2hpgJuxBW/gyfmtBnUai fnggx3EE3ev8HTysZU9q0h+TJwwJKGv6sUc8qcTGFDtavnnl+r6xDUY7A6GvXEsSoCEEynby 72byGeSovfq/4AWGNPBG1L61Exl+gbqfvbECP3ziXnob009+z9I4qXodHSYINfAkZkA523JG ap12LndJeLk3gfWNZfXEWyGnuciRGbqESkhIRav8ootsCIops/SqXm0/k+Kcl4gGUO/iD/T5 oagaDh0QtOd8RWSMwLxwn8uIhpH84Q4X1LadJ5NCgGa6xPP5qqRuiC+9gZqbq4Nj Message-ID: <3e5cd446-3527-17ef-9ab8-d6ad01d740d0@gmx.com> Date: Thu, 21 Nov 2019 09:51:26 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="z17Ov8C1sqjzhPJ9kFI9oGxMRJOTO8ZgQ" X-Provags-ID: V03:K1:n0tw9N2SticFHbjUEiwyemVvaVK3c03MGEgm9EfMt1uZedgsjOn 5930r+oFpSiWjKCUMb7iNBSShMSkcZntbkPyDaemffkA85+Z/UKAGmhTCgL2wBlG4CdJfDu yU0ivtrFhZv6+P+uLhzWP1hQPK8vDAKu28hgENhx49AcIo1zac8GozpxHlzxrbbipLxQKRz a6L3i0XJ6cG/Ggww3GOTA== X-UI-Out-Filterresults: notjunk:1;V03:K0:ABUhbPb3JpU=:8KPdrTKfTYQNrX/KChKYHe RhSWfc9X2TXqxr6FK1zKmyE3xgFIJ1VxAYE89GyILh1r2UI8UL9K8eDyak4CIR3MzErAZuG8x bQmlcyIW+YlQNKznao2wdBgCMC9znnmv/YzqKhg4dDjfR9PXu2JC5fzP0QEdq3cl3aE4w2/bJ 4SCV0C6lU5/l2+Cda4GLNJL7y9lbba3kiIU4GBkA42t7tPHUdmJgXxz3U6yW+dzDeIuFAqv8Z wlj0fHxWt2eGT0zaperHZEtkzDg0ek8SJnqll7T97h9hDDmHqvM/rChPEin/IJHeyW04fuG0u dZgqIIiIYfgzl4uMSshs6LMTGtANvQ3nxc+8fdxu3qwUferx77kK13wKb6Wn+RUz4GrVEFfFZ ccdb8w3n3NhK8q2z+H6rxGbYMxiC1XnuBHxyyi+wdtFuRb7RHpVvv80I5SjFLXShLRcF/eNVV zwFJcq3cPrxR02gg1MGpDQWO1w4OJH09DhGh0acSwDfNkFeZ5iMFPnEsGmUUe8npN7qKEKP0T JLmINkrDEzjVTQTibCr3j0iElKvkSS+XTbxAsDLQ4GQyDZWbTRxNh/z/lCfuH0HKo/corhOTH 6W5jas0m3oUB7PH1YcO4hCbtD6G1dChzJa9sL8xUPu1eRAkiT0BkSsHGPex1cRgFQsiRdSd8L hgG73IaGMj5gCVJb+q1DPL2igxPBRMGsGpbF67HpCdhlHTmhblOIpFSxDEPGocY+1kqOxxGZ/ X5dwBZtHgDM7vZQLzrk3pM3R3JTAS9tc3PyehnsyKoNvLmlu7rkKgkHEw/zLudPBVszDma1Uj 7JSUqd3szNEC+wqPXodv6vRsBG/6bDwEY8oewXzNWsh6FR6e1HpmwddeS961xPXSVb59ijImd b17L+29pe6fPz7vlWw0Jshw4Pw0bbtOKq7xeE5kTUi7fvu0BDZ8q+FxVa+ILPOO6zoU9XBKoH eDnjM02YbAg+/LMIzS80wSHVY+2km/59ulwAyLCLp1Jw4uTd6DQGWElTPk3MmL1CnxtgtxQnk 0IXvRr1Z/1mknqqHoT2JSpJBJXqt7OdpFjNp11+utgEsAXyqS0UDxrzYNh9ZL4pKdMKelv7Ci lcz4aXceM3tTXT4lNu/i+EpXQWH9PHEE73tdzT+36LZLKjY1GfByoPe0C/jY0F0QbpeKR5JuU ajTkPsl5CybcPvjExrI+73bQAMDRCIcJYUb02d5pKoLLcHYAWDTe3HwkrNTuxNqADuEjzgmiP PfG+yBiS7v4E+sAD7LXHmY0xZqxksq9bHCLP8dF8eigHreybn1zyPjIhSGRU= Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --z17Ov8C1sqjzhPJ9kFI9oGxMRJOTO8ZgQ Content-Type: multipart/mixed; boundary="1zS7lcwe1UTBMmy64vzvIan2e0uoASz7D" --1zS7lcwe1UTBMmy64vzvIan2e0uoASz7D Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 2019/11/21 =E4=B8=8A=E5=8D=8812:36, Christian Pernegger wrote: > Hello, >=20 > I've decided to go with a snapshot-based backup solution for our new > Linux desktops -- thank you for the timely thread --, namely btrbk. > A couple of subvolumes for different stuff, with hourly snapshots that > regularly go to another machine. Brilliant in theory, less so in > practice, because every time btrbk runs, the box'll freeze for a few > seconds, as in, Firefox and LibreOffice, for instance, become entirely > unresponsive, games hang and so on. (AFAICT, all it does is snapshot > each subvolume and delete ones that are out of the retention period.) >=20 > I'm aware that having many snapshots can impact performance of some > operations, but I didn't think that "many" <=3D 200, "impact" =3D stop > dead and "some operations" =3D light desktop use. These are decently > specced, after all (Zen 2 8/12 core, 32 GB RAM, Samsung 970 Evo Plus). > What I'm asking is, is this to be expected, does it just need tuning, > is the hardware buggy, the kernel version (Ubuntu 18.04.3 HWE, their > 5.0 series) a stinker, something else awry ...? Are you using qgroup? With qgroup, snapshot deleting is still a problem though. (But not for snapshot creation, that shouldn't cause any slow down, unless you're using multi-level qgroups) Thanks, Qu >=20 > Cheers, > C. >=20 --1zS7lcwe1UTBMmy64vzvIan2e0uoASz7D-- --z17Ov8C1sqjzhPJ9kFI9oGxMRJOTO8ZgQ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEELd9y5aWlW6idqkLhwj2R86El/qgFAl3V7Z4ACgkQwj2R86El /qgunwf+JzpL19RmwVHCBLoCMUXRux3tg8GkL1SPB1ejb0mgpNoRTS/kpgmVi0Dm nHU2CjgNgU7PfIKD7KBymBvLKkAcU15aDPe6QzjbwBTXgHYc1TFRMF5jKEl+tLsp JktFX7Eh3M4mUYI+WLUqd3k/VDuZ8RZl1AnH5TTQSWvwO0KB/OKhm6ct9S9ppbX5 kdgkCE8ALR9Dz9US7r3l2dMaqYj/SGszVdIMqKuzRa+rX9AoOZf2sBbf5SjrsASR evLUgybjvY4h1NPQHlDzCiDULkRLxlk/QGugrMFpWdP57uhLyz60QXbDP1zP5Hjv TWxiJSr+Ytcs2MLkC4e2E4oEFEfrsg== =ty7f -----END PGP SIGNATURE----- --z17Ov8C1sqjzhPJ9kFI9oGxMRJOTO8ZgQ--