Subject: Re: [Gnu-arch-users] Re: [GNU-arch-dev] [ANNOUNCEMENT] /Arch/ embraces `git'

From: Denys Duchier <[email-masked]>
Date: Thu, 21 Apr 2005 11:09:58 +0200

Tomas Mraz <[email-masked]> writes:

> If we suppose the maximum number of stored blobs in the order of milions
> probably the optimal indexing would be 1 level [0:2] indexing or 2
> levels [0:1] [2:3]. However it would be necessary to do some
> benchmarking first before setting this to stone.

As I have suggested in a previous message, it is trivial to implement adaptive
indexing: there is no need to hardwire a specific indexing scheme.  Furthermore,
I suspect that the optimal size of subkeys may well depend on the filesystem.
My experiments seem to indicate that subkeys of length 2 achieve an excellent
compromise between discriminatory power and disk footprint on ext2.

Btw, if, as you indicate above, you do believe that a 1 level indexing should
use [0:2], then it doesn't make much sense to me to also suggest that a 2 level
indexing should use [0:1] as primary subkey :-)

Cheers,

-- 
Dr. Denys Duchier - IRI & LIFL - CNRS, Lille, France
AIM: duchierdenys