From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f46.google.com ([74.125.82.46]:64670 "EHLO mail-wg0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753010Ab3EZMDL (ORCPT ); Sun, 26 May 2013 08:03:11 -0400 Received: by mail-wg0-f46.google.com with SMTP id l18so3624350wgh.1 for ; Sun, 26 May 2013 05:03:10 -0700 (PDT) Message-ID: <51A1F9FD.7000807@gmail.com> Date: Sun, 26 May 2013 14:03:09 +0200 From: "xavier.gnata@gmail.com" MIME-Version: 1.0 To: Duncan <1i5t5.duncan@cox.net> CC: linux-btrfs@vger.kernel.org Subject: Re: compression on external hard drive? References: <51A1372B.6060402@gnata.eu> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 05/26/2013 04:23 AM, Duncan wrote: > Xavier Gnata posted on Sun, 26 May 2013 00:11:55 +0200 as excerpted: > >> Nowdays, external hard drives are mounted automagically by kde, gnome or >> whatever else. >> How is it suppose to work with external hard drives using btrfs with >> compression? >> If a btrfs filesystem lzo-compressed is mounted without the >> |compress=|xxx option then all the newly created files are uncompressed, >> aren't then? >> Would it be possible to detect if a file system is compressed and to >> mount it *automatically* and accordingly (except otherwise explicitly >> stated by the user) with/without the lzo/gzip option? > There's a proposal to do something like ext3/4's default options as set > by tune2fs, at some point, presumably before btrfs loses the "unstable > disk format" and under heavy development warnings. However, there's > nothing like that yet, AFAIK, so most options must be set per-mount. > > There's a lot you can do with udev events, however, and strongly suspect > either compression-detection, or match-against-a-list-and-compress (or > don't compress if the default is compression otherwise) if the UUID/LABEL > is listed. > > Alternatively, at least kde can be set not to automount specific UUIDs/ > LABELs, and then there's always the traditional fstab option, and I think > either fstab entered drives are ignored by the automount system or > they're automounted with options from fstab (I have that kde subsystem > entirely disabled here so it doesn't automount anything, so I'm not sure > which it actually does). > Ok I'm going to play with udev event and have a lot at what kde4.10.3 can do. However, I hope this will be solved at fs level once the dust has settled. Xavier