| |
POWER4 L3 cache
- On-chip tag (IBM calls it directory), off-chip data
- 32 MB/8-way associative/512 bytes line
- Contains eight coherence/snoop controllers
- Does not maintain inclusion with L2: requires L3 to snoop fabric interconnect also
- Maintains five coherence states
- Putting the L3 cache on the other side of the fabric requires every L2 cache miss (even local miss) to cross the fabric: increases latency quite a bit
POWER4 die photo
|
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
|
|
|
|
