Status: Tags: Links: Comparing ISAs Criteria - Data Memory
Memory access
Principles
Most time constraining aspect of program execution ?
- due to transfer rate limitation of bus between memory and microprocessor
- Register access is faster than memory since register is inside CPU
Von Neumann bottleneck ?
- When memory is accessed during fetch stage
- During decode and execute stages
- Value may be read or written
Calculating total memory access ?
- Calculate fetch + decode/execute
Fetch
?
- Based on the length of each instruction
- If an instruction is worth 3 words, then 3 fetches
Decode/Execute
?
- Decode for each variable used
- Execute to store
Examples
How many memory accesses
?
How many memory accesses
?
References:
Created:: 2022-03-21 20:33