pl/pgsql performance

Hi All

I have one big Pl/Pgsql function (about 1500 line code) , i can divided it
to about 5 part and call each script from main script . In this case i
need to know which way is faster .

and some question about pgsql :

1- is pgsql engine open one process for each script ?
2- how i can chose max connection number for pgsql server based on cpu core
and RAM capacity that have maximum Efficiency?

Thanks and Best ergards.