Multi-core Processor Jia Yao ECE Dep. Auburn University

What is a multi-core processor ? A processing system composed of two or more independent cores, which facilitates simultaneous managing of activities. CPU1 and L1 Cache CPU2 and L1 Cache L2 Cache Main Memory Dual-core Architecture Dual-core and quad-core processor High performance without driving up power consumption

Multi-core processor history Motivated by increasing operating frequency, which leads to increasing gap between processor and memory speeds, larger cache, higher power consumption. The world’s first multi-core processor is “Power4” released by IBM in IBMPower4, Power5, Power6, PowerPC AMDAthlon, Opteron, Phenom IntelCore 2 Duo, Core 2 Quad, Xeon NvidiaGeforce9, Geforce200 Sun microsystemMARJC, UltraSPARC

Advantages ? Single-core Large tasks running simultaneously slow down Dual-core Large tasks can be processed in separate CPUs CPU CPU1 CPU2

How does multi-core processor work? Significant improvement on cache (bus) snooping Signals between different CPUs travel shorter distance, which allows more date sent in one period, less signal degradation, does not need to sent data repeatedly as often CPU1 and L1 Cache CPU2 and L1 Cache L2 Cache Main Memory = 2? Not exactly, 1+1=1.5

Future Development Low Power Design power consumption doubles with each doubling of operating frequency Software support Such like more intelligent compiler which is capable of sending balanced load of instructions to individual cores.

Reference [1] [2] Fruehe.pdfhttp:// Fruehe.pdf [3] -Core_WP_en.pdfhttp://multicore.amd.com/Resources/33211A_Multi -Core_WP_en.pdf [4] [5] Architecture.htmlhttp:// Architecture.html