Simulation performance may be improved with set()/update() when
- The current mirrored value is the same as the desired given by
set(). Then no bus transactions happens. - you want to write to multiple fields of a register that are not individually selectable. Writing to multiple fields of register creates multiple read/modify/write transactions. You can use
set()to the individual fields and then update then entire register.
Normally you would just apply set() any field/register in the entire register model, and then call a single update() on the entire model.