long transaction

Hi there,

I have a script which includes 30000 called functions within a single 
transaction.

At the beginning, the functions runs fast enough (about 60 ms each). In 
time, it begins to run slower and slower (at final about one per 2
seconds).

I check the functions that runs slowly outside the script and they run 
normally (60 ms each).

What is the problem ?

TIA,
Sabin