[plt-scheme] getting better speed with JIT

[Prabhakar Ragde]

Will Clinger recently posted in comp.lang.scheme on the speed of various 
Scheme implementations, and mentioned in passing that one has to 
(require mzscheme) to get the JIT to work. I was not aware of this. I 
cannot find this incantation anywhere in Help Desk, except in the mzc 
manual. Should I have known this, and if so, what did I miss? It sped up 
one of my benchmarks, a double loop looking for perfect numbers, by a 
factor of 2.5. Thanks. --PR