On pipelining dynamic instruction scheduling logic
Jared Stark, Mary D. Brown, Yale N. Patt · 2000
A machine's performance is the product of its IPC (Instructions Per Cycle) and clock frequency. Recently, Palacharla, Jouppi, and Smith [3] warned that the dynamic instruction scheduling logic for current machines performs an atomic operation. Either you sacrifice IPC by pipelining this logic, thereby eliminating its ability to execute dependent instructions in consecutive cycles. Or you sacrifice clock frequency by not pipelining it, performing this atomic operation in a single long cycle. Both alternatives are unacceptable for high performance.