Re: [reiserfs-dev] Re: Ext2 directory index: ALS paper and benchmarks

[Ragnar Kjørstad]

On Sat, Dec 08, 2001 at 12:01:20AM +0300, Hans Reiser wrote:
> >In the cases I've studied more closely (e.g. maildir cases) the problem
> >with reiserfs and e.g. the tea hash is that there is no common ordering
> >between directory entries, stat-data and file-data.
> >
> >When new files are created in a directory, the file-data tend to be
> >allocated somewhere after the last allocated file in the directory. The
> >ordering of the directory-entry and the stat-data (hmm, both?) are
> >
> 
> no, actually this is a problem for v3.  stat data are time of creation 
> ordered (very roughly speaking)
> and directory entries are hash ordered, meaning that ls -l suffers a 
> major performance penalty.

Yes, just remember that file-body ordering also has the same problem.
(ref the "find . -type f | xargs cat > /dev/null" test wich I think
represent maildir performance pretty closely)

-- 
Ragnar Kjørstad
Big Storage