How much benefit do the models actually provide? Other than ISel my processor now has an enormous ROB, and a huge number of execution units, I've never really n

How much benefit do the models actually provide? Other than ISel my processor now has an enormous ROB, and a huge number of execution units, I've never really noticed anything super dramatic from compiler instruction scheduling. MCA is basically useless for most programmers because it can't model the memory accesses i.e. cache performance.