This is a list of Alpha EV6 CPU's performance counter event types. Please see alpha architecture reference
| Name | Description | Counters usable | Unit mask options |
| CYCLES | Total cycles | all | |
| RETIRED | Retired instructions | 1 | |
| COND_BRANCHES | Retired conditional branches | 1 | |
| BRANCH_MISPREDICTS | Retired branch mispredicts | 1 | |
| DTB_MISS | Retired DTB single misses * 2 | 1 | |
| DTB_DD_MISS | Retired DTB double double misses | 1 | |
| ITB_MISS | Retired ITB misses | 1 | |
| UNALIGNED_TRAP | Retired unaligned traps | 1 | |
| REPLAY_TRAP | Replay traps | 1 |
Measurement is a crucial component of performance improvement since reasoning and intuition are fallible guides and must be supplemented with tools like timing commands and profilers.- The Practice of Programming, Brian W. Kernighan and Rob Pike