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Rewritten ReiserFS 4 Promises 2-5x Speed Increase
An anonymous reader reports that version 4 of "ReiserFS will be released in first quarter. Complete rewrite will support Atomic writing. 2-5 times faster. File corruption will be a thing of the past. Lindows.com is paying for part of it."
Or if that is too much to digest, I wrote a fairly easy to follow summary on kuro5hin.
- I don't need to go outside, my CRT tan'll do me just fine.
Yes-- this is far too late to save ReiserFS on my installation. I moved all our disks to ext3 a few months ago after experiencing extensive file corruption. A scsi disk went bad. When it went down, all files that had been active at the time were corrupted. Mostly that was several dozen mail spool files. Didn't I switch to a journaled file system in part to avoid this sort of thing? Grrrrrrrrrr.
Both ext3 and reiser3 offer(ed) data journaling, which would help with that kind of thing. Neither of them would even try to provide any better protection against corruption than if the application program(s) crashed. If a drive failed while applications were writing to files, the files might be current as of the most recent completed system call (write() or whatever), but even then, they could be "corrupt" in the sense that not all the operations in a sequence had completed; I do not think even reiser4 offers that level of transactional support-- I guess maybe it could have some sort of open()...close() atomicity thing, which would be nice.
Larry
Ext3 in its default mode also does metadata journaling only, but it always writes the data blocks first (at some performance hit), so such lossage won't occur.
In theory, you may lose data badly during a power failure on a non-journaling filesystem such as ext2, since the filesystem itself may be badly broken. However, this does not occur often in practice.
In short, reiser3 is probably not the data-eating monster in normal operating conditions, nor will the filesystem become corrupted in case of a power failure, but newly rewritten data can get lost (including the older versions) during a crash or power failure, so it is probably safer to use ext3 for now if you don't have a UPS. Also, if your disk fails, all bets are off --- expect to lose some data, no matter how advanced your filesystem is (unless it is designed to operate on faulty hardware).
BTW, I dumped reiserfs on my disk (on my home machine) during a disk failure because it doesn't have the feature to mark blocks as "bad". Quite a few blocks on my disk mysterically went bad, and for some reason it was not corrected by the hard drive.
I was a little unclear. The kernel crashed because of the bad disk. After replacing the disk, rebooting, and replaying the journals, we found Reiser had corrupted data on other, still-good disks. I would certainly expect to lose data that had been scheduled to be written at the time of the crash. I did not expect to have files on good disks essentially shuffled up with each other, which was the form of the data corruption.
CNR also works better than apt-get in that it installs the programs for you but it also puts icons where they make sense so you don't have to go searching for them if (like me) you're not a hard-core Linux guru.
Make sure you guys try LindowsOS before you knock it. It's really getting good!!!
Have you hugged your penguin today?
The 'atomic update' quality is something MySQL and PostgreSQL can take advantage of, or in fact any lication that often writes small amounts of data and calls fsync/fdatasnc. And it shouldn't be terribly difficult to make the required changed. Kudos!
Yeah, probably a little more than an AC post on
Personally, I've used ReiserFS exclusively since it first became available (and supported) with SuSE, which was few years ago, and I haven't experienced any problems with it. In fact, I was able to successfully save my data even when my IBM DeskStar (aka "Deathstar") HD started going bad - didn't lose anything.