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=-3.3 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, FORGED_MUA_MOZILLA,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 97A0FC433E1 for ; Tue, 18 Aug 2020 00:10:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7748220789 for ; Tue, 18 Aug 2020 00:10:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726713AbgHRAKP (ORCPT ); Mon, 17 Aug 2020 20:10:15 -0400 Received: from static.214.254.202.116.clients.your-server.de ([116.202.254.214]:47198 "EHLO ciao.gmane.io" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726314AbgHRAKN (ORCPT ); Mon, 17 Aug 2020 20:10:13 -0400 Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1k7pCd-00049E-7w for linux-btrfs@vger.kernel.org; Tue, 18 Aug 2020 02:10:11 +0200 X-Injected-Via-Gmane: http://gmane.org/ To: linux-btrfs@vger.kernel.org From: Andrew Skretvedt Subject: Re: compress-force mount option documentation is ambiguous Date: Mon, 17 Aug 2020 19:10:05 -0500 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 In-Reply-To: Content-Language: en-US Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 8/17/20 3:18 PM, Peter Kese wrote: > The `compress-force` mount option which states: > > "If compress-force is specified, then compression will always be > attempted, but the data may end up uncompressed if the compression > would make them larger." > Meanwhile, on my system (Linux Mint 18.3 Sylvia (tracks Ubuntu Xenial)), the manpage for `mount` (July 2014 - util-linux 2.27.1), in the section on btrfs-specific mount options says: > If compress-force is specified, all files will be compressed, > whether or not they compress well. If compression is enabled, > nodatacow and nodata‐ sum are disabled. While experience suggests to me I shouldn't necessarily consider `man 8 mount` authoritative for every filesystem supported, the reality that inexperienced users will consult it for authoritative advice suggests that every effort must be made to keep its information in-sync with documentation published elsewhere. Alternatively, it's specific authoritativeness could be called out and then refer the user to where the most current details can be found, e.g. `man 5 btrfs`. This is kinda done already, as `man 8 mount` does say, immediately under its FILESYSTEM-SPECIFIC MOUNT OPTIONS header: > What options are supported depends a bit on the running kernel. > More info may be found in the kernel source subdirectory > Documentation/filesystems. as a catch-all. *shrug* -- OpenPGP 0xC6901B2A6C976BB3 (https://keys.openpgp.org)