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Btrfs Is Not Yet the Performance King

Posted by timothy on from the happy-churning dept.

Ashmash writes "Benchmarks of the Btrfs filesystem have been published by Phoronix that compare it to the XFS, EXT3, and EXT4 file-systems. In the end they conclude that this next-generation Linux filesystem is not yet the performance king. In a great number of the tests, the EXT4 filesystem that was designed to be an interim step to Btrfs actually performs much better than the unstable Btrfs, albeit Btrfs still has more advanced features. Fedora 11 even took longer to boot when using Btrfs than EXT3 or EXT4."

11 of 117 comments (clear)

  1. Re:hmm by TooMuchToDo · · Score: 3

    Where's the "-1, tired and worn out" mod option?

  2. Stability, reliability by Hatta · · Score: 4, Insightful

    I don't care which filesystem is fastest. Kcryptd is the bottleneck on my system, so it really doesn't matter how fast the filessytem is. I want to know which filesystem is the most robust. What filesystem is least likely to lose data?

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    1. Re:Stability, reliability by Cassini2 · · Score: 5, Informative

      btrfs has several features that help prevent data loss, and in particular silent corruption of data on the disk. It is also handy to be able to take snapshots for backup purposes.

      Ext3 and Ext4 are faster because they omit some of these features. There was recently some heated debate about ext4 and data loss, see the Slashdot discussion for more links.

      With file systems, speed and data integrity are trade-offs.

    2. Re:Stability, reliability by TooMuchToDo · · Score: 3, Informative

      Unfortunately, Sun had no plans on licensing ZFS so it could run on Linux. Will Oracle change it's mind? Probably not, hence the reason btrfs is reproducing features of ZFS.

    3. Re:Stability, reliability by onefriedrice · · Score: 4, Insightful

      I think it's important to keep in mind that it is the GPL that is incompatible with other free licenses, not the other way around.

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    4. Re:Stability, reliability by Anonymous Coward · · Score: 3, Informative

      Yes, ZFS is a perfect example of a design that's perfect by its own definition of perfect. For (perfect) example, you can perfectly accidentally add an empty USB drive to a pool and you'll be perfectly unable to ever remove that device without doing a perfectly full mirror or backup.

      They've been promising to fix this any day now for years. I'll send you $50 when they do. I'll send you another $50 when I can use it on my Linux box.

      I think my money's perfectly safe.

    5. Re:Stability, reliability by Anarke_Incarnate · · Score: 3, Informative

      I'm glad that you can assume a performance margin without knowing the workload or the application. Please, enlighten us with the performance of ZFS using Oracle or another database...Sure it can be fast, but please, in detail, explain the tunables that need to be set to achieve this performance and what kind of issues you may have with fsync and such, especially when dealing with SAN storage with external battery backed cache..... I am curious..... (and yet know the answers).

    6. Re:Stability, reliability by Nevyn · · Score: 4, Insightful

      You're right, Sun had no idea their new license would be incompatible with Linux because they wanted to be compatible instead of doing the slimy thing and trying to make it be a selling point over using Linux, which everyone was doing. Alas. for them RMS and Linus travelled back in time and created/used the GPL just to thwart poor Sun.

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  3. How is this news? by Burkin · · Score: 3, Insightful

    What is newsworthy in the fact that a less tested and less stable filesystem is slower than filesystems that are more mature, stable and well-tested?

  4. Numbers for mysql performance on BTRFS? by Smidge207 · · Score: 3, Insightful

    Btrfs is mainly created for the Oracle client that doesn't want to use "raw device". It's to improve performance reading/writing large files with high concurrency. So it have to be fast on concurrent request.

    What should be looked is :
    how mysql perform on BTRFS
    how postgres perform on BTRFS
    how firebird perform on BTRFS

    As there is no magical solution, btrfs is no exception. It's not a general usage FS as is ext (imho). On the desktop, xfs will be the way to go. Performance-wise it's obviously not so great (I do realise that it's still in development and this might change in the future), and the features it delivers are not very interesting as well imho, except maybe for the online defragmentation thingy. But I'm not an enterprise user whis is what this fs aims at I assume.

    Still I appreciate the work. Let's hope it doesn't get axed now that Oracle owns Sun and thus already has ZFS.

    cheers

    =Smidge=

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  5. Re:format stability by pigeon768 · · Score: 4, Informative

    Extents and delayed allocation are the big ones, both of which are available in ext4, reiser4, and btrfs.

    Unfortunately, xfs is more likely to eat data in individual files than ext3 or ext4 w/ data=ordered. It's apparently less likely to end up with an uncorrectable superblock.

    xfs is also horrifically slow for random access of smaller files. If your application calls for massive files, such as databases or a porn library, xfs is preferable over reiserfs or ext3, comparable to ext4, but for general use you're better off with ext3/4 or reiserfs. (by reiserfs I mean 3.6, not reiser4. I can't speak for reiser4)

    It's important to remember that there is no one fs to rule them all. Any time anyone tells you "*fs is the best filesystem" they're suffering from fanboyism. xfs is probably not the ideal filesystem for / on a desktop system, but it's a great filesystem for a partition on a server running a database or a fileserver serving large files, or for a DVR application like mythtv.