[ILUG] ReiserFS bugs

[Wesley Darlington]

Hi,

On Sat, Dec 02, 2000 at 12:46:28PM +0000, Niall O Broin wrote:
> I was stress testing a new RAID subsystem with a 200GB Reiser FS running a
> script called stress.sh that I found somewhere (takes a tree of data, by
> default /usr/doc, puts an md5sum of every file in it into a file, then runs
> parallel copies (by default 4, though I was running 8) of that tree on to
> the FS to be stressed, puts an md5sum of every file in each copy into a
> file, and diffs each of those files against the original md5sum file). It's
> a reasonably stressful test - the load on an 850 MHz Athlon is around 10.
> I've run this three times so far. Twice it was on a Reiser FS and each time
> the machine hung - load went up to nearly 20 (before top stopped
> refreshing), disk lights were all out after about 1 hour and 3 hours. 

Sounds to me like an athlon problem. Is your power supply up to the task?

> On the advice of the RAID subsystem vendor, I retried the test on an ext2
> filesystem and it ran overnight with no problems (well, that's a lie, there
> was occasional output from the diff, but I think that if you're copying that
> amount of data, an occasional bit error is not surprising).

I wouldn't find the `occasional bit error' at all acceptable.

> This is a little distressing, to say the least, particularly since I have a
> production box with a Reiser FS (although it's somewhat smaller than this one)
> 
> I just started another test on a Reiser FS and I got an error like the
> following:
> 
> wait_buffer_until_released: nobody releases buffer (dev x7441, size 4096,
> blocknr 5570560, count 3, state(UPTODATE, CLEAN, UNLOCKED)). Still waiting
> (4800000)  JDIRTY !JWAIT

Reiserfs stresses your hardware more than ext2, so they say. If you've got
flakey hardware (and I think you do!) then you'll have more problems with
reiserfs than with ext2.

> According to the RAID vendor

I'd be more inclined to blame the [athlon] computer than the raid vendor.

> Have any of you using Reiser on big filesystems (Dave Rynne ?) noticed any
> problems or glitches of any kind. I just had a look in the messages on my
> production box and I don't see any instance of this error, nor have I
> noticed anything untoward, but the existence of this problem has me worried.
> A little googling returned a number of references to the problem, but no
> suggestion as to its severity.

I don't have reiserfs on any filesystems that size. Have you tried the 
array on another non-athlon, known-good box? Like a dell server? ;-)

Your hardware is broken, imho. Either the computer, the raid array, or
whatever joins them together.

ATB,
Wesley.