A copy-on-write (COW) file system developed by Oracle included in the Linux kernel.

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2
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1answer
780 views

Boot partiotionless disk with syslinux

A file system can be configured to span a complete disk, omitting any partition table. Notice intentionally the command to do so does not use /dev/sda1 but the raw, unpartitioned device instead. ...
1
vote
1answer
130 views

strange directories on ubuntu 13.10 btrfs partition

I am running Ubuntu 12.04 (ext4) and installed Ubuntu 13.10 on a partition of its own (sda2) with btrfs. I had no time to configure 13.10 to my work environment (yet), so I mounted /dev/sda2 from ...
2
votes
0answers
144 views

What's status of btrfs as root fs? [closed]

What is the current status of btrfs being the root filesystem including /boot; meaning that you do not need to create a separate /boot partition. I ask because I noticed on Debian 7 you cannot setup ...
0
votes
1answer
91 views

btrfs: mismatching generation and generation_v2 found in root item

I am seeing this message in dmesg: btrfs: mismatching generation and generation_v2 found in root item I found a related question here: Understanding btrfs dmesg However, unlike that question, I ...
3
votes
1answer
800 views

How to delete btrfs subvolumes with <FS_TREE> in their name

I have a bunch of btrfs snapshots like so: 20:17:37 [root@galaxy /]$ btrfs subvolume list -a / |grep apt ID 271 gen 348 top level 5 path <FS_TREE>/@apt-snapshot-2013-04-17_21:44:30 ID 272 gen ...
2
votes
1answer
432 views

Linux btrfs how to remove unexistent filesystem from list?

I'm giving a try to btrfs. As newbie I did some mistakes, which are good for learning! I created several btrfs filesystems upon different devices (sdX, loop, lvm, etc). During these tests, I removed ...
5
votes
3answers
750 views

Why can't a regular user delete a btrfs subvolume

Using a loop-mounted user created btrfs filesystem, with the permissions set correcly, a user is able to freely create btrfs subvolumes: user@machine:~/btrfs/fs/snapshots$ /sbin/btrfs sub create ...
2
votes
1answer
389 views

btrfs, infamous ENOSPC error while doing a backup from a snapshot

My system is Fedora 19 x86_64 w/3.10.7 kernel. I am trying to use a btrfs snapshot for backing up my /, like this: #!/bin/bash btrfs subvolume snapshot / /snap/ tar -cvf - /snap 2>/dev/null | ...
2
votes
0answers
322 views

System cannot boot, continiously scanning btrfs filesystem

On the previous boot I installed HAL to make amazon prime video streaming work, which it did (mostly), but after reboot the system could not pull itself up all the way to BASH and drops to a failed ...
1
vote
1answer
148 views

Does a high “used” value for a device in “btrfs filesystem show” pose a problem? Should a balance operation be performed?

I have a laptop with a Samsung 840 500 GB SSD, and I've installed openSUSE 12.3 with btrfs as the filesystem. A few days ago I first got a message from my web browser about it not being able to save ...
3
votes
1answer
625 views

Understanding btrfs dmesg

Based on the documentation I found at https://btrfs.wiki.kernel.org/index.php/Data_Structures I am strugeling to understand the following dmesg [ 173.946830] device fsid ...
2
votes
1answer
582 views

Can btrfs handle different RAID levels for different subvolumes?

I'd like to assign different RAID levels to different subvolumes in my btrfs filesystem, eg have a subvolume /home that uses RAID 1 and a subvolume /var that uses RAID 0. Is that at all possible (if ...
9
votes
4answers
1k views

Why is cp --reflink=auto not the default behaviour?

Why is cp --reflink=auto not the default behaviour? Could it cause any harm to enable it? Is it possible to enable it at compile time, so it is used all across the system, not just in interactive ...
5
votes
0answers
312 views

btrfs change after system upgrade broke apt-btrfs-snapshot [closed]

After upgrading (via apt-get dist-upgrade) a Mint 14 Linux box to Mint 15, apt-btrfs-snapshot seems to have stopped working: 18:25:48 [root@galaxy ~]$ apt-btrfs-snapshot list Sorry, your system lacks ...
8
votes
3answers
5k views

How to get rid of the “scanning for btrfs file systems” at start-up?

After upgrading from Ubuntu 12.04 to Ubuntu 12.10, I get a message "scanning for btrfs file systems" at starting-up. I don't have any BTRFS filesystem. It delays the booting for about 15 seconds. How ...
5
votes
1answer
753 views

btrfs and the discard mount option on an ssd

I can't seem to find an answer to this so I thought I would ask here: In /etc/fstab and when using the mount command in ext4 you would add the option discard to activate TRIM on an SSD. Similarly ...
1
vote
1answer
189 views

Deleting files on btrfs through smb

I have set up a btrfs multidisk which I mount and have shared on the network through smb. Whenever someone deletes a file on the share in windows, it seems to be rather slow. Any ideas/options I need ...
4
votes
0answers
418 views

Compiling and running Snapper for Ubuntu

I am trying to get snapper working in my Mint 14. (The version from launchpad is old and not compatible with Ubuntu 12.10. The OpenSuSe's build project failed to build it, too). So I try my luck with ...
3
votes
1answer
189 views

Equivalent of pvmove for BTRFS

Similar to the question I asked a while back. This one's a little easier? I can see there's volume management logic in BTRFS for removing/adding/rebalancing physical drives, but is there a tool to ...
0
votes
2answers
587 views

Unknown btrfs error, partition won't mount

unix friends, a day or so ago my btrfs partition just stopped working, which means i can't mount it anymore which is why my Fedora Linux doesn't boot anymore. I don't really have much information, ...
2
votes
1answer
405 views

Will using a compressed filesystem over an encrypted volume improve performance?

Encryption/decryption is often the main bottleneck when accessing an encrypted volume. Would using a filesystem with a fast transparent compression (such as BTRFS + LZO) help? The idea is that there ...
7
votes
4answers
7k views

Should a laptop user switch from ext4 to btrfs?

Related to this. I'd like to take advantage of an OS switch to upgrade to BTRFS. BTRFS claims to offer a lot (data-loss resiliency, self-healing if RAID, checksumming of metadata and data, ...
0
votes
1answer
132 views

Btrfs subvolume questions

Just a few questions about Btrfs: Do I have to mount a Btrfs filesystem before creating subvolumes on it? Can I easily convert an existing directory into a subvolume? (i.e. if I want to make "/home" ...
5
votes
2answers
2k views

How to clone btrfs filesystem into different medium preserving snapshots' sharing data

I have decided to give btrfs raid capabilities a try. I set up a btrfs with sudo mkfs.btrfs -m raid10 -d raid10 /dev/sda9 /dev/sdb9 /dev/sdc9 /dev/sdd9 Now I want to clone my existing btrfs ...
2
votes
1answer
1k views

Graphical Btrfs tool

Is there a graphical tool for creating Btrfs sub-partitions and in particular, subpartitions like "GParted" or "system-config-lvm"? I'm running Debian squeeze. In response to the first comment, Btrfs ...
6
votes
1answer
1k views

Move a linux instalation using btrfs on the default subvolume (subvolid=0) to another subvolume

When doing a installation to a root btrfs filesystem, many linux distributions install to the default subvolume. If left unmodified, this layout will force any snapshots or subvolumes to be created ...
16
votes
3answers
1k views

Securely delete files on btrfs filesystem

Sometimes, there's the need to delete a file in a filesystem, and make sure that the file is truly gone. A file that contains sensitive passwords, for example, should be throughly wiped from the disk. ...
1
vote
2answers
602 views

btrfs performance

I decided to mess around with btrfs and found some weird performance anomalies. The tests I've done are with with two external hard drives one formatted with ext4 the other btrfs. ext4 performance ...
1
vote
2answers
282 views

How to debug/audit which devices cache writes?

I store documents on btrfs partition built upon sparse dm-crypt device located on ext4 main partition on physical harddrive. When kernel panics (and this happens on daily basis on my ASUS P53E with ...
3
votes
1answer
312 views

Online remount btrfs of root filesystem with different subvolume (snapshot)

Let's say you have a btrfs root filesystem on an online system. You want to revert the filesystem to an earlier state, of which you have a snapshot: remount /dev/sdaX / -o remount,subvol=snapshots/Y ...
6
votes
1answer
1k views

Are there any deduplication scripts that use btrfs CoW as dedup?

Looking for deduplication tools on Linux there are plenty, see e.g. this wiki page. Allmost all scripts do either only detection, printing the duplicate file names or removing duplicate files by ...
3
votes
0answers
137 views

How does SuSE Linux's support for btrfs differ from Ubuntu and Fedora's?

The SuSE Linux Enterprise Server 11 Service Pack 2 release notes state that SuSE offers "commercial support" for btrfs, while Ubuntu and Fedora appear to be holding back until a working fsck utility ...
3
votes
1answer
2k views

Clear unused space with zeros (btrfs)

How to clear unused space with zeros ? (I am asking for tool for btrfs filesystem) I'm looking for something smarter than cat /dev/zero > /mnt/X/big_zero ; sync; rm /mnt/X/big_zero Like ...
0
votes
1answer
2k views

File system jfs/btrfs/xfs/ext4 [closed]

I was looking into some of the requirement, where huge amount of recursive files are written and deleted and looking forward if any FS (file system) as such gives advantage on others. I am trying to ...
8
votes
2answers
969 views

What keeps one side of an rsync so busy?

I've got a Debian machine on my LAN serving as a backup server for the others. It has four HDDs combined into a software RAID 5 md device, on that an LVM, and on that btrfs. Backups are made using ...
4
votes
2answers
756 views

btrfs on openSUSE not releasing disk space

I have an openSUSE 12.1 install on my main desktop running with btrfs filesystem for root (/boot is ext4). I started having issues today with KDE informing me that disk space is almost all gone and ...
8
votes
4answers
910 views

Why does my desktop lock up when I copy lots of files to a USB drive?

My desktop is usually very responsive, even under heavy load. But when I copy files to a USB drive, it always locks up after some time. By "lock up", I mean: Moving focus from one window to another ...
4
votes
1answer
3k views

When using btrfs, why “Size”, “Used” and “Avail” values from df do not match?

I have a btrfs partition. When I run df -h, it shows: Filesystem Size Used Avail Use% Mounted on /dev/sda2 113G 101G 8.3G 93% /home From Why is that? Is it because reserved space for ...
1
vote
1answer
365 views

Can't mkdir /root (btrfs)

I performed a standard Debian install using wheezy/testing netinst iso for amd64. After the install completed I booted into a live environment so that I could snapshot the root as a btrfs subvolume ...
2
votes
1answer
246 views

Incomplete factory update makes btrfs filesystem unusable?

After an incomplete update from the factory repo my opensuse 12.1 btrfs filesystem is unusable. I have plenty of disk space free but zero inodes. When I try to delete or create a file it gives me the ...
2
votes
2answers
2k views

How to remove an empty directory (btrfs filesystem)?

I'm using the experimental btrfs filesystem. My directory looks like this: ls -la empytfolder total 4 drwxr-xr-x 1 root root 0 19. Mär 14:00 . drwxr-xr-x 1 root root 298 19. Mär 13:59 .. I ...
3
votes
1answer
6k views

How do I fix btrfs? [closed]

I've trawled mailing lists and finally finished up on Ubuntu's btrfs page, and am left feeling that btrfs still does not have a full fixing utility (as indicated on their home page). Even though ...
21
votes
9answers
3k views

How to keep track of changes in /etc/

I would like to keep track of changes in /etc/ Basically I'd like to know if a file was changed, by yum update or by a user and roll it back if I don't like the chage. I thought of using a VCS like ...
4
votes
1answer
2k views

Why does btrfs allow to create a raid1 with mismatched drives?

I'm creating a btrfs using sudo mkfs.btrfs -m raid1 -d raid1 <small-disk> <large-disk> or sudo mkfs.btrfs -m raid1 -d raid1 <large-disk> <small-disk> it creates the fs with ...
8
votes
2answers
3k views

How to create a snapshot in btrfs, and then rollback to it after some work?

What are the commands to use in btrfs in case I want to: create a (read-only) snapshot of a volume; (do some experiments in the volume); and then rollback the volume to the snapshot?
6
votes
3answers
2k views

How to create a read-only snapshot in btrfs?

As far as I understand, the snapshots made by btrfs subvolume snapshot are writable by default and are visible at a certain path under the mountpoint of your btrfs volume. How to setup the system so ...
13
votes
2answers
3k views

What are the advantages of Btrfs for end users?

Btrfs has begun to gain some momentum in replacing ext4 as the default filesystem of choice for a few distributions such as Fedora Core 16. It is experimentally available in a number of other ...
2
votes
3answers
351 views

Uncopyable 5GB file, BTRFS

I have a 5.3GB tar file, located on a BTRFS partitioned eSATA drive. When trying to copy the file to another disk, or expand the tar the process seems to freeze. No errors are generated, and waiting ...
12
votes
5answers
2k views

Is btrfs stable enough for home usage? [closed]

btrfs has finally found its way into the latest kernels, is it considered stable and safe enough to use in a home backup scenario (as an alternative to zfs) ?