From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ud10.udmedia.de ([194.117.254.50]:32938 "EHLO mail.ud10.udmedia.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756211AbcARSeA (ORCPT ); Mon, 18 Jan 2016 13:34:00 -0500 Date: Mon, 18 Jan 2016 19:27:17 +0100 From: Markus Trippelsdorf To: Omar Sandoval Cc: linux-btrfs@vger.kernel.org Subject: space_cache=v2 on root fs Message-ID: <20160118182717.GA321@x4> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hi, while testing the new space_cache=v2 mount option it looks like my root fs doesn't automatically create the new space cache. I'm using the following /etc/fstab: UUID=7ef56edc-673e-452e-9e05-3fabf074168b / btrfs noatime,compress=lzo,space_cache=v2 0 0 UUID=6b7d75bf-3d12-409c-88ed-500ac6b78510 /var btrfs compress=lzo,space_cache=v2 0 0 UUID=24cee7e4-9093-4f86-aa73-d8a59d7f3c6c /var/tmp btrfs compress=lzo,space_cache=v2 0 0 During first mount the space cache was created for /var (/dev/sdb2) and /var/tmp (/dev/sda3), but apparently not for / (/dev/sdc3): Jan 18 18:48:18 x4 kernel: BTRFS info (device sdb2): enabling free space tree Jan 18 18:48:18 x4 kernel: BTRFS info (device sdb2): using free space tree Jan 18 18:48:18 x4 kernel: BTRFS: creating free space tree Jan 18 18:48:18 x4 kernel: BTRFS info (device sdb2): setting 1 ro feature flag Jan 18 18:48:18 x4 kernel: BTRFS: checking UUID tree Jan 18 18:48:18 x4 kernel: BTRFS info (device sda3): enabling free space tree Jan 18 18:48:18 x4 kernel: BTRFS info (device sda3): using free space tree Jan 18 18:48:18 x4 kernel: BTRFS: has skinny extents Jan 18 18:48:18 x4 kernel: BTRFS: detected SSD devices, enabling SSD mode Jan 18 18:48:18 x4 kernel: BTRFS: creating free space tree Jan 18 18:48:18 x4 kernel: BTRFS info (device sda3): setting 1 ro feature flag Jan 18 18:48:18 x4 kernel: BTRFS: checking UUID tree Jan 18 18:48:22 x4 kernel: BTRFS info (device sdc3): enabling free space tree Jan 18 18:48:22 x4 kernel: BTRFS info (device sdc3): using free space tree During subsequent boots the "enabling free space tree" message is repeated every time for the root fs. Jan 18 18:53:48 x4 kernel: BTRFS info (device sdb2): using free space tree Jan 18 18:53:48 x4 kernel: BTRFS info (device sda3): using free space tree Jan 18 18:53:52 x4 kernel: BTRFS info (device sdc3): enabling free space tree Jan 18 18:53:52 x4 kernel: BTRFS info (device sdc3): using free space tree markus@x4 tmp % mount /dev/sdc3 on / type btrfs (rw,noatime,compress=lzo,ssd,noacl,space_cache=v2,subvolid=5,subvol=/) devtmpfs on /dev type devtmpfs (rw,relatime,size=4080208k,nr_inodes=1020052,mode=755) proc on /proc type proc (rw,relatime) sys on /sys type sysfs (rw,relatime) devpts on /dev/pts type devpts (rw,relatime,gid=5,mode=620) none on /dev/shm type tmpfs (rw,relatime,size=409600k) /dev/sdb2 on /var type btrfs (rw,relatime,compress=lzo,noacl,space_cache=v2,subvolid=5,subvol=/) /dev/sda3 on /var/tmp type btrfs (rw,relatime,compress=lzo,ssd,noacl,space_cache=v2,subvolid=5,subvol=/) -- Markus