Preserving Inclusion Explicitly

• Propagate lower-level (L2) replacements to higher-level (L1)

  • Invalidate or flush (if dirty) messages

• Propagate bus transactions from L2 to L1

  • Propagate all L2 transactions?
  • use inclusion bits?

• Propagate modified state from L1 to L2 on writes?

  • if L1 is write-through, just invalidate
  • if L1 is write-back
    • add extra state to L2 (dirty-but-stale)
    • request flush from L1 on Bus Rd

Previous slide

Next slide

Back to first slide

View graphic version