S/390 microprocessor design

The technical, business, and market requirements for large enterprise servers (“mainframes”) strongly influence the design of microprocessors for these systems. Specific characteristics of the ESA/390 and z/Architecture instruction set architectures lead to different pipeline and branch prediction strategies than are found in most other microprocessors. The requirements for robust, scalable performance across a wide range of workloads, highly efficient logical partitioning, and very high hardware reliability affect the cache structure, internal code, and hardware fault detection and recovery designs.