[NTLUG:Discuss] picking a filesystem in 2006...

[Wayne Walker]

On Fri, Sep 08, 2006 at 10:43:36AM -0500, Richard Geoffrion wrote:
> In a different thread Chris wrote:
> >Since I've run 2TB filesystems for awhile using reiserfs, 
> >I can say it works well (2TB because historically I was 
> > using LVM1).
> 
> >From that I gather LVM1 had a 2TB limit.
> 
> >I'd make sure that your ext2 utilities are up to date.  
> > <SNIP>
> 
> >If you just can't stand reiserfs (v3), I'd probably look at
> xfs and jfs.  
> 
> I have this to say about ext3 and reiserfs as it relates to using dirvish.  ext3 outperforms reiserfs by..oh..it has to be 4000% if not more!   There is some fundamental underlying process that makes reiserfs slow when running dirvish-expire to remove the 'vaults'.  Hmm..let me see if I can re-google the answer.... hang on a second.
> 
> {music plays in the background}
> 
> Ok...I'm back..sorry it took so long.  I wasn't able to find the whys-and-wherefores but I did find a benchmark test that shows some of the results.   I dunno.. when I try to remove a large directory it takes forever on reiserfs.  And let's talk talk about mounting times!  wow!  ext3 is dang near instant where ReiserFS takes so loooooooongggg.  (benchmarkes - http://linuxgazette.net/102/piszcz.html )

Being quite old, I suspect that the benchmark above did not have
"dir_index" turned on.  That would make dramatic differences in
find/create files/directory speeds.

Run "dumpe2fs /dev/sd??" and see if you have dir_index turned on.
Your distro may not turn it on by default but if you are dealing with
directories with Lots of files or directories in them, it's important.

> >I still believe there is a major fundamental bug inside of
> >ext2 (and therefore 3 as well).  Times I've lost an ext3 
> >filesystem, the results were NOT pretty at all.
> 
> What fundamental bugs?  Google searches only bring up OS/Distro version bugs and debunk these unwritten fundamental bugs that no one deems worthy to quote.  :)
I too have heard about bugs in ext2/3 but never seen it substantiated.

> ><snip>
> >The reiserfs boxes are infinitely more flexible, since the 
> >LVMs and filesystems can be resized without unmounting.  
> >A nifty thing in the enterprise.
> 
> Hmm...Isn't ext3 resizeable?  I see where others talk about it.
Yes, I've resized filesystems on our production servers, while the file
system is mounted and in use.

> Scary...it just seems real scary to trust data to something so new when there are so many other options available.  Now...if it was the only solution or for use in non-critical data...I could see it.
Bleeding performance is nice, but reliability is what you want.  There
are good tools fro ext2/3 and for xfs and jfx, but reiserfs was short on
tools like salvage tools and recovery tools last I looked.

> reiserfsck is relatively fast.   The problem comes in when one has to do 
> a --rebuild tree!  It takes a day on a 230 GB volume!  It'll take WEEKS 
> to do a 4TB volume!  That is unacceptable!    Hey..that's what I need -- 
> a benchmark on the filesystem that fsks the fasted.
OMG

-- 

Wayne Walker

www.unwiredbuyer.com - when you just can't be by the computer

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