>
> On its own, I can understand that Fb may want to use as much
> CPU as it has. However, in the light of relatively modest
> usage by mysql or postgres (both averaging CPU load at 1.5-5%
> everyday), the argument does not hold.
>

Wrong. ALL database engines (Including MySQL) will use 100% of CPU if they
need to. Whenever they are on the CPU, they use 100% for that instant. If
the job takes some time, your measurement tools (top,systat -vmstat, etc)
indicate it ramping up it's CPU usage).
This is why you're seeing the 1.5% - 5% usage - they don't spend much time
at 100%. If you did give them a difficult query, you'd see them pegged at
100% as well.

> Furthermore, shouldn't FB be more I/O intensive than CPU intensive?

This depends on your schema, indexes, and the query you're trying to do.
If you're doing a stored procedure that calulates pi, it'll be CPU bound.
If you've done a select * from a table returning BLOB fields from it, it'll
be I/O bound.

Nige.