How to increase stack size for unreal engine?

Hi Alex:
Thanks for ur reply, so helpful. I found it finally in LinkEnvironment.cs as follows.
///


/// The default stack memory size allocation
///

public int DefaultStackSize = 5000000;
Can i ask one more question? what’ the unit of DefaultStackSize? bit or byte. actually, i think 5000000 is enough. can u give me a recommended number? Thanks a lot.