Posted by David T. Ashley on 07/08/06 03:52
"Richard Levasseur" <richardlev@gmail.com> wrote in message
news:1152322021.658752.74530@b28g2000cwb.googlegroups.com...
> Another option would be to name the file after the primary key, or
> other unique index, of the table.
The reason for the prime moduli directory scheme is that Unix directory
operations become inefficient beyond a few hundred entries in a directory.
The prime moduli scheme is designed to avoid this by filling up the
lowest-level directories evenly.
It isn't clear that naming the file after the primary key would have the
same advantage.
The example I gave was with three primes. In practice, one should use
primes not larger than 200 and enough of them so that their product exceeds
2^32.
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