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Journalling File System Comparison

Posted by timothy on from the which-does-what-how-fast dept.

Ithika writes "Justin Piszcz recently did an analysis of some common journaling file systems over at Linux Gazette. Due to the Gazette's ridiculous restrictions on image filesize all of the graphs are pretty much illegible, however. You can see the article as the author originally intended here."

10 of 38 comments (clear)

  1. How about a little consistency... by llefler · · Score: 3, Insightful

    One graph has ext2 first, the next has xfs. ext3 is light blue in one, purple in the next. I quickly found that after having to recheck the key for each graph, I really didn't care anymore.

    --
    It is amazing what you can accomplish if you do not care who gets the credit. -- Harry Truman
    1. Re:How about a little consistency... by MBCook · · Score: 3, Insightful
      I agree. The constant switiching between virticle and horizontal bar graphs was annoying and unneccessary too. I also don't think that the one or two 3D bar graphs should have been there.

      My only other complaint is the image size, but that was explained and I understand. I suggest that if at all possible you read the author's link because the smooshed graphs can be rather illegible.

      Small gripes aside, good article.

      --
      Comment forecast: Bits of genius surrounded by a sea of mediocrity.
  2. Reiser4, and why Ext2 is there by MBCook · · Score: 4, Insightful
    I've seen these kind of things before, but what I'd really like to see is Reiser 4. While I know it's not released yet, you can download the beta and I'd like to see how it performs compared to other filesystems.

    Otherwise, an interesting article.

    And for the complainers who say "Why include ext2, everyone should use a journaling filesystem", there are two reasons. First is that ext2 is a MAJOR STANDARD that was what everyone used for years and years. The second is that ext2 is still usefull. For a temporary filesystem (like /tmp or some temporary RAM disk with unimportant contents) ext2 is often very fast because it lacks all the journaling stuff which is unimportant for a temporary filesystem.

    --
    Comment forecast: Bits of genius surrounded by a sea of mediocrity.
    1. Re:Reiser4, and why Ext2 is there by jgardn · · Score: 2, Insightful

      Just because you have the space doesn't mean it is organized. The filesystems are a way of organizing and managing the data into the neat file and directory paradigm you are used to.

      As far as RAM disk versus SHM, there are occasions where you would like to copy files and store shared files in RAM, especially on systems with plenty of it to spare and busy hard drives.

      --
      The radical sect of Islam would either see you dead or "reverted" to Islam.
    2. Re:Reiser4, and why Ext2 is there by 0x0d0a · · Score: 2, Insightful

      And for the complainers who say "Why include ext2, everyone should use a journaling filesystem", there are two reasons. First is that ext2 is a MAJOR STANDARD that was what everyone used for years and years. The second is that ext2 is still usefull. For a temporary filesystem (like /tmp or some temporary RAM disk with unimportant contents) ext2 is often very fast because it lacks all the journaling stuff which is unimportant for a temporary filesystem.

      Also, because ext2 was used for so long and is not changing much, most people have a pretty good idea how well it performs, and thus can make good comparisons regarding it.

      --
      May we never see th
  3. It'd be cool by dtfinch · · Score: 4, Insightful

    If there was a spreadsheet to go with that. One could normalize the results and weight each benchmark according to their performance needs. And there are differences between the 2.4 and 2.6 kernels' IO handling that could make an fs perform better on one kernel than the other.

    But since he's done this all for free, all I can say is thanks.

  4. FS corruption by ReyTFox · · Score: 4, Insightful

    One test that wasn't in the article was a reliability test - i.e. if something bad happens, how much is lost? Or just as importantly, can you guarantee the FS will work as long as the storage device does?

    I've noticed that many people seem to have a bias against ReiserFS for being a less stable FS. There is some truth to that, I suppose, since it's newer, but I've poked around google for hard facts, and couldn't really find any evidence from the past 1 to 1-1/2 years of particular problems with *any* of the major filesystems. All I came up with were anecdotes, and not only that: There were just about as many with horror stories about ext2 and ext3 as with Reiser!!!

    So I wouldn't worry about corruption unless it's already happened to you; experience is the best teacher :P

    1. Re:FS corruption by Phouk · · Score: 2, Insightful

      [...] I've poked around google for hard facts, and couldn't really find any evidence from the past 1 to 1-1/2 years of particular problems with *any* of the major filesystems. All I came up with were anecdotes, and not only that: There were just about as many with horror stories about ext2 and ext3 as with Reiser!!! [...]

      As ext2/ext3 are probably much much more widely used than ReiserFS, if there are the same absolute number of problems reported with both, that would of course speak strongly against ReiserFS's reliability.

      --
      Stupidity is mis-underestimated.
  5. Re:Use the filesystem that fits by UPi · · Score: 2, Insightful

    Exactly. What I've seen from all the colored bars is that there are no extreme differences for most usage patterns between the filesystems. ext3 seemed surprisingly slow in some (regular) tests, but otherwise all the journaling filesystems seemed rather evenly matched.

    I wouldn't recommend choosing a filesystem based on this benchmark because it showed that the speed is basically the same within ~20%.

    Is there a benchmark that shows some real difference between these filesystems? Like how they recover from regular disc corruption patterns?

  6. All the tested filesystems reasonably mature by bangular · · Score: 2, Insightful

    All of the filesystems tested are pretty mature. Reiserfs had some early 2.4 kernel issues (but then again, what didn't!). JFS is the "youngest" of all those (Well, JFS on linux anyway). A filesystem would have to be of pretty shitty design these days to have random corruption issues. You'd be more likely to have hard drive issues before random filesystem corruption issues.