[darcs-users] always long comment

Samuel A. Falvo II sam.falvo at falvotech.com
Tue Jul 13 14:27:17 UTC 2004

On Tuesday 13 July 2004 01:40 am, Juliusz Chroboczek wrote:
> > After a lot of changes to a project, this directory can get pretty
> > large, which will perform poorly on some filesystems.
> That's a pet peeve of mine.  Hashtables have been known since the
> 1960s, B-trees since the early 70s.  Why are there still filesystems
> that use linear search in directories?

Because linear searches are much easier to implement, and do not consume 
nearly the amount of space that even a hashtable would.

> There's a vicious circle here.  Because for so many years filesystem
> designers didn't know their job, programmers worked around that by

I don't think you have enough credentials to be able to make this claim 
with certainty.

> At last, we've got reasonable filesystems.  So please, please use
> Reiserfs, use XFS, heck, even JFS, but don't request that people build
> yet another database within every application.

Bingo.  The real blame is not with the filesystem designers.  The real 
blame is with those who install the operating system, and choose a 
sub-optimal filesystem for their needs, knowing full well that the 
filesystem is going to be used quite heavily.

I installed ReiserFS largely out of curiosity.  However, I've been 
extremely happy with it.  But even then, ReiserFS isn't the end-all and 
be-all of filesystems (nor is XFS, JFS, et al.).  What would be ideal is 
if we could eliminate filename searches all-together.  There is NO need 
to always have to refer to a file by name.  inode number is plenty 
sufficient, especially for tightly bound records.  Of course, the only 
disadvantage to this is that you lose the ability to move and copy some 
files, as not all files will be listed in a directory.  Thus, to achieve 
this kind of flexibility without sacrificing the ability to move/copy 
whole files around, you end up once again having a filesystem inside a 

See?  There ARE technological reasons for this stuff.  It's not just a 
matter of whim.

What I want to know is, why the hell are we still using filesystems at 
all, and not an orthogonally persistent operating system, where *ALL* of 
this would become moot anyway?

Samuel A. Falvo II

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