Which parameter of EP and BPM should be changed when end user increase Significantly

hi All

We are using System EP and BPM.

The number of users will increase.

Would please tell us Which parameter of EP and BPM should be changed when end user increase Significantly.

For example, heapmemory parameter,Max thread.

Please give us advice and Info.

system info

EP: nw 7.02

BPM:nw ce 7.20.

Thanks in advance,

Rongtao