Summary and Conclusions

• Caches are essential to gain the maximum performance from modern microprocessors
• The performance of a cache is close to that of SRAM but at the cost of DRAM
• Caches can be used to form the basis of a parallel computer
• Bus-based multiprocessors do not scale well: max nodes
• Larger-scale shared-memory multiprocessors require more complicated networks and protocols

CC-NUMA is becoming popular since systems can be built from commodity components (chips, boards, OSs) and use existing software

e.g. HP/Convex, Sequent, Data General, CRAY, Sun, ICL

(Acknowledgements: Andrew Bennett wrote the first version of this chapter)