Processor Speeds

Question 1

Processor Speeds

Answer 1

• Real speed: CPU clock
  
  • Historical qualification of speed
  • Megahertz (Mhz) Gigahertz (Ghz)
• Actual Speed
  
  • Combination of different factors
  • Clock speed, CPU architecture, bus speeds, bus width, L1 cache size, L2 cache size, operating system capabilities

Question 2

CPU Cache

Answer 2

• Superfast memory
  
  • Holds data, instruction, and or results
• Level 1 cache (First check)
• Level 2 cache (secondary data)
• Level 3 cache (still on the chip)
  
  • Shared between all cores

Question 3

Hyper-Threading

Answer 3

• Hyper-threading technology (HTT)
• One CPU acts like two
• Doesn’t actually work as fast as two
  
  • 15% - to 30% performance improvements
• Operating System must be written for HTT
  
  • Windows XP or later

Question 4

Virtualization Support

Answer 4

-Run other operating systems within a single hardware platform

• Virtualization in software was limited
  
  • Performance and hardware management challenges
• Virtualization added to processor
  
  • Intel Virtualization Technology (VT)
  • AMD Virtualization (AMDv)

Question 5

32bit vs 64bit

Answer 5

• Data width
  
  • Data path, integer size, memory address
• Larger bus size moves more data
  
  • 64bit bus moves twice as much data as 32bit

-Software must be optimized to take advantage of 64bit architectures

Question 6

NX bit

Answer 6

• No-Execute bit
  
  • Intel = XD bit (execute disable)
  • AMD = Enhanced Virus Protection
• Designation sections of memory as executing code or data
  
  • Code cannot run from protected memory =
  • Prevents malware and viruses from executing

-The OS must support this feature