Re: Parallel example for computing pi efficiently is actually slow

[treeform]

It uses threads to do very little amount of work: 4 * math.pow(-1, k) / (2*k + 
1) ... creating a thread is a very heavy weight operation, while doing little 
math is really easy. So most of the time is spent doing thread bookkeeping. 
Your computation needs to justify running it in a thread ... which this does 
not as its just an example for parallel not an efficient implementation.