Serializing instructions in system-intensive workloads: Amdahl’s Law strikes again
Philip M. Wells, Gurindar S. Sohi · Proceedings - International Symposium on High-Performance Computer Architecture/Proceedings · 2008
Serializing instructions (SIs), such as writes to control registers, have many complex dependencies, and are difficult to execute out-of-order (OoO). To avoid unnecessary complexity, processors often serialize the pipeline to maintain sequential semantics for these instructions.