1. Hyper-Threading Aili Shen ENG 11 TED TALK

2. To Be Tackled Hyper-Threading Concepts Hyper-Threading Architecture Advantages/Disadvantages Applications 3. What is Hyper-Threading At each point of time only a part of processor resources is used for execution of the program code. Unused resources can also be loaded, for example, with parallel execution of another thread/application. Extremely useful in gaming and 3-D rendering applications where many threads are used. 4. Threading Algorithms Multiprocessing Distribute the load over many processors Adds extra cost Simultaneous multi-threading Multiple threads execute on a single processor without switching. Basis of Intels Hyper-Threading technology. 5. Hyper-Threading Architecture First used on certain Intel Pentium 4 and Intel Xeon processors Makes a single physical processor appear as multiple logical processors. Each logical processor has a copy of architecture state. Logical processors share a single set of physical execution resources 6. Hyper-Threading Architecture Operating systems and user programs can schedule processes or threads to logical processors as if they were in a multiprocessing system with physical processors. 7. Advantages Extra architecture only adds about 5% to the total die area. No performance loss if only one thread is active. Increased performance with multiple threads Better resource utilization. 8. Disadvantages To take advantage of hyper-threading performance, serial execution can not be used. Threads are non-deterministic and involve extra design Threads have increased overheat Shared resource conflicts 9. References Intel Hyper-Threading Technology Review www.digit-life.com/articles/pentium4xeonhyperthreading/ HyperThreading Threads Its Way into Application http://www.tomshardware.com/cpu/20021227/ Introduction to Multithreading, Superthreading and Hyperthreading http://www.arstechnica.com/paedia/h/hyperthreading/hyperthreading- 1.html