Write Policy
  • write through
    • The data is written to both the cache and to main memory.
    • Simpler to implement.
    • Can use write buffers to reduce stalls.
    • Cache and main memory are consistent.
  • write back
    • The data is written to only the cache. The modified cache block (dirty bit set) is written to main memory when it is replaced.
    • Reduces main memory traffic.
Chapter 7: Large and Fast: Exploiting Memory Hierarchy - 23 of 67