Computer Architecture By Chris Van Horn

CPU Basics “Brains of the Computer” Fetch Execute Cycle Instruction Branching

Control Unit Manager Sends signals to other devices telling them what to do

System Clock Signals when it is ok to perform work Cannot base CPU performance strictly by system clock Computer A: 12 cycles/instruction 1 Ghz Computer B: 3 cycles/instruction 250 MHz

Registers User Registers Control Registers –Program Counter –Instruction Register –Status Flag –Stack Pointer

ALU Where the real work happens –Adder –Multiplier –Shifter –Etc.

The Bus Provides Transportation –Data –Control Signals 3 Parts of the Bus Other Bus Types Master/Slave relationship

Interrupts Interrupts processor when something needs its attention Threading

Pipelining Works like an assembly line Potential for large speed increase Long vs. Short Pipelines Drawbacks

Memory Hierarchy –Registers –Cache Level 1 Level 2 –Main Memory –Magnetic Disks

Multi Core Fun Why multi core? Why not just jack up the clock speed?

Intel

Intel Multi-core Technology Hyper-Threading Dual Core Core Duo

Hyper-Threading Dual core for the poor Processor runs two threads at once

Intel Dual Core Two Complete Cores running at same frequency Intel Pentium D –2.8 – 3.4 GHz –FSB 800 MHz –Cache (per core) 900 Series 2MB 800 Series 1MB

Intel Core Duo Replacement for Pentium M Specs –2MB L2 cache shared –1.5 – 2.16 GHz –FSB 667 MHz

AMD

AMD Dual Core Technology Design Started Early Direct Connect Architecture Operton Dual Athlon Dual-Core X2

Opteron Specs –1.8 – 2.4 GHz –L1 cache 64 KB per core –L2 cache 1 MB per core –FSB 1GHz

Athlon Dual-Core X2 Specs –2.0 – 2.4 GHz –L1 Cache 128 KB instruction 128 KB data –L2 Cache 1-2MB per core –1 GHz FSB

Dual-Core Duel AMD challenges Intel to a Duel (Opteron Vs. Xeon) Intel Refuses Tests Run by SPEC (Standards Standard Performance Evaluation Corporation )

Test Results AMD declared itself the winner Lack of Results Reporting may be skewed

CNET X2 vs. Pentium D CNET independent test AMD won every round of tests Why?

Tests Run Everyday Computing –Office Productivity (SysMark Scores) –Internet Content Creation (SysMark Scores) Gaming –Halflife 2(fps) Multitasking –Encoding Video while Virus Scanner running (time to complete both) Photo Editing –Photoshop (resizing large photos) MP3 Encoding –iTunes (time to encode album) Video Encoding –Sorenson Squeeze 4 (time to encode video)

Price Vs. Performance