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Benchmarking Linux Filesystems In New 2.6 Kernel

Posted by michael on from the file-it-away dept.

An anonymous reader writes "KernelTrap has an interesting article about a recent benchmark conducted to compare five journaling filesystems available with the current 2.6.0-test2 Linux development kernel. The tests were conducted with a very simple shell script, mainly timing how long it takes to copy, tar, and remove directories. Looks like reiser4 is the fastest filesystem at the expense of consuming much more CPU, with ext3 trailing a ways behind."

10 of 56 comments (clear)

  1. fs issues by Tirel · · Score: 4, Insightful

    speed is nice, but I think the more important question is; how stable is it?

    1. Re:fs issues by BrokenHalo · · Score: 5, Informative
      I don't know about 2.6 yet, but Reiserfs hasn't let me down so far.

      For a long time I resisted moving away from ext2, as I didn't want the journalling overhead and didn't mind the occasional e2fsck. After I got a few power outages I changed my mind :-) but I haven't been disappointed with Reiserfs' speed.

  2. karma for Anonymous Coward by Anonymous Coward · · Score: 5, Informative

    The first item number is time, in seconds, to complete the test (lower
    is better). The second number is CPU use percentage (lower is better).

    reiser4 171.28s, 30%CPU (1.0000x time; 1.0x CPU)
    reiserfs 302.53s, 16%CPU (1.7663x time; 0.53x CPU)
    ext3 319.71s, 11%CPU (1.8666x time; 0.36x CPU)
    xfs 429.79s, 13%CPU (2.5093x time; 0.43x CPU)
    jfs 470.88s, 6%CPU (2.7492x time 0.20x CPU)

    What's interesting:
    * ext3's syncs tended to take the longest 10 seconds, except
    * JFS took a whopping 38.18s on its final sync
    * xfs used more CPU than ext3 but was slower than ext3
    * reiser4 had highest throughput and most CPU usage
    * jfs had lowest throughput and least CPU usage
    * total performance of course depends on how IO or CPU bound your task is

    1. Re:karma for Anonymous Coward by dustman · · Score: 4, Interesting

      I think another interesting metric to look at would be cpu time used. If one of them took 90% CPU for 10 seconds, that would be a big winner imo.

      reiser4 171.28s @ 30% CPU = 51.384s CPU
      reiserfs 302.53s @ 16% CPU = 48.4048s CPU
      ext3 319.71s @ 11% CPU = 35.1681s CPU
      xfs 429.79s @ 13% CPU = 55.8727s CPU
      jfs 470.88s @ 6% CPU = 28.2528s CPU

  3. Speed is not of the essence by mnmn · · Score: 5, Informative

    There are other things about filesystems us sysadmins to know about. Which is the most stable and crashproof filesystem? Ive suspected it to be XFS from which I recovered data after doing dd if=/dev/zero of=/dev/hda1 count=2048576

    Also what filesystem would require the lest or no syncing at all? Befs?

    In server environements with stripped 15K cheetah SCSI drives, you'd worry more about stability than speed.

    --
    "Give orange me give eat orange me eat orange give me eat orange give me you." -Nim Chimpsky
  4. Incomplete comparison? by Futurepower(R) · · Score: 4, Interesting


    From the article:
    "reiser4 171.28s, 30%CPU (1.0000x time; 1.0x CPU)
    reiserfs 302.53s, 16%CPU (1.7663x time; 0.53x CPU)

    What's interesting:
    * reiser4 had highest throughput and most CPU usage"

    The comparison seems incomplete to me. Reiser4 took about half the time, with twice the CPU usage. The

    Total Work Done by the CPU = Percent * Time.

    Reiser4 did the work in half the time, but the total work was roughly equal. Actually, ReiserFS was more efficient considering total CPU cycles.

    1. Re:Incomplete comparison? by makapuf · · Score: 5, Insightful

      Except that if you have a mostly idle CPU and your task is more & more waiting for the disk to complete, you don't care about 11 or 30 % if the other 89 or 70 % of the CPU are idle.

      Comparing CPU cycles needed is NOT a fair benckmark, unless your task is CPU _AND_ IO Bound.(if it's not io bound, take whatever fs you have, it doesn't matter.)

      The benchmark was right in giving results as TWO parameters : CPU used and time spent. Might be interesting to see how it depends of the drive type or the CPU arch, though)

  5. Blah... This was on lkml... by j.e.hahn · · Score: 5, Informative

    And a number of people complained that it wasn't a great benchmark. Hans Reiser admitted it was just a quickie, and I forget who it was that said it, but ext3 has some performance enhancements that are on the cusp of merging into Linus' tree from the -mm kernels.

    Wait until 2.6 is out folks. These numbers are still open for mass fluctuation.

  6. Oracle posted some stats by Stone316 · · Score: 5, Informative

    With respect to filesystems and database performance. EXT3 came out on top.

    --
    "Thanks to the remote control I have the attention span of a gerbil."
  7. CPU Usage?! by metalmaniac1759 · · Score: 4, Funny

    30%-40% CPU Usage - whoa. What happens to poor me - with a PIII 550 MHz, 128 MB SDRAM and KDE running all the time.

    I switched from RedHat to Gentoo and KDE stopped crawling. God knows what will happen with ReiserFS4.

    Nandz.