From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f45.google.com ([74.125.82.45]:43092 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751295AbdJaQXm (ORCPT ); Tue, 31 Oct 2017 12:23:42 -0400 Received: by mail-wm0-f45.google.com with SMTP id m72so14807656wmc.0 for ; Tue, 31 Oct 2017 09:23:42 -0700 (PDT) Received: from debox (bzq-109-64-142-30.red.bezeqint.net. [109.64.142.30]) by smtp.gmail.com with ESMTPSA id s6sm1675211edd.23.2017.10.31.09.23.39 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 31 Oct 2017 09:23:39 -0700 (PDT) Message-ID: <1509467017.1662.37.camel@gmail.com> Subject: Several questions regarding btrfs From: ST To: linux-btrfs@vger.kernel.org Date: Tue, 31 Oct 2017 18:23:37 +0200 Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hello, I've recently learned about btrfs and consider to utilize for my needs. I have several questions in this regard: I manage a dedicated server remotely and have some sort of script that installs an OS from several images. There I can define partitions and their FSs. 1. By default the script provides a small separate partition for /boot with ext3. Does it have any advantages or can I simply have /boot within / all on btrfs? (Note: the OS is Debian9) 2. as for the / I get ca. following written to /etc/fstab: UUID=blah_blah /dev/sda3 / btrfs ... So top-level volume is populated after initial installation with the main filesystem dir-structure (/bin /usr /home, etc..). As per btrfs wiki I would like top-level volume to have only subvolumes (at least, the one mounted as /) and snapshots. I can make a snapshot of the top-level volume with / structure, but how can get rid of all the directories within top-lvl volume and keep only the subvolume containing / (and later snapshots), unmount it and then mount the snapshot that I took? rm -rf / - is not a good idea... 3. in my current ext4-based setup I have two servers while one syncs files of certain dir to the other using lsyncd (which launches rsync on inotify events). As far as I have understood it is more efficient to use btrfs send/receive (over ssh) than rsync (over ssh) to sync two boxes. Do you think it would be possible to make lsyncd to use btrfs for syncing instead of rsync? I.e. can btrfs work with inotify events? Did somebody try it already? Otherwise I can sync using btrfs send/receive from within cron every 10-15 minutes, but it seems less elegant. 4. In a case when compression is used - what quota is based on - (a) amount of GBs the data actually consumes on the hard drive while in compressed state or (b) amount of GBs the data naturally is in uncompressed form. I need to set quotas as in (b). Is it possible? If not - should I file a feature request? Thank you in advance!