Better disk workload balance can be acquired in the homogeneous system, consequently, relative workload balance status can be reached in various nodes of the system.
Because it is far easier to automate one script running through an open, homogeneous system than many different scripts across a heterogeneous one, standardization is the key to automation.
So, that's a homogeneous system, one phase. You have to know if your system is an equilibrium system or not.
equivalent homogeneous system