Increasing ulimit stack size benefits?

Hello I'm new in Linux and at my work I have a server that runs a banking software. The company that made the software said that the stack size should be set to unlimited. Does this make the software have a better performance if I set it to unlimited? For now it is 10240 and the end of day rollover process takes like two hours and a half to finish and I'm trying to find a way to make it shorter. Thank you in advance.