[igraph] time eastimation

[Ragia .]

Hi,
I used igraph to i Implemented Independent cascade model (Greedy algorithm), 
running the code on a small network (Round 2k N )..it seems endless.
kindly,
how can I estimate time needed for the program to run..and how I determine 
server specification to run the program and get results in appropriate time.

thanks in advance
Ragia