simulating high load for vacuum full

I'm trying to diagnose a problem that happened during vacuum full.

It is a programming problem triggered by some lock, delay whatever,
happening during vacuum.

Making large updates to a bunch of tables is a PITA just to obtain a
slow VACUUM FULL.

Restoring a "fragmented" DB doesn't look as a working strategy.
The restore shouldn't be fragmented.

What are the "side effects" of a vacuum full?
Any cheaper way to cause a heavy vacuum full or just its side
effects?

thanks

-- 
Ivan Sergio Borgonovo
http://www.webthatworks.it