Cache Memory

Introduction

Cache memory is a small, fast memory that stores frequently accessed data to reduce the average time to access data from the main memory.

Cache Organization

Types of cache mapping techniques:

• Direct Mapped Cache
  • Simple and fast
  • Fixed mapping
  • Potential for conflicts
• Set Associative Cache
  • Balanced approach
  • Reduced conflicts
  • N-way set associative
• Fully Associative Cache
  • Most flexible
  • Complex implementation
  • No conflicts

Cache Policies

Important cache policies:

• Replacement Policies
  • LRU (Least Recently Used)
  • FIFO (First In First Out)
  • Random Replacement
• Write Policies
  • Write-through
  • Write-back
  • Write-allocate
  • No-write-allocate

Cache Performance

Factors affecting cache performance:

• Hit Rate and Miss Rate
• Hit Time and Miss Penalty
• Cache Size
• Block Size
• Associativity

Important Concepts