How to use InitialAllocationCount in the Particle Emitter?

[Noah_Z]

This value allows for the user to declare the number of particles that should be allocated at initialization of the emitter. If it is 0, the calculated peak count is used. (Since the calculated value can result in a higher than required count, this parameter is supplied to allow tighter memory control.)

But it does not work for me. The particle number does not change at all even if I set this value to 5.

How to use it please?