cc-metric-collector/collectors/likwid/groups/phi/CPI.txt
2021-03-25 14:47:10 +01:00

24 lines
619 B
Plaintext

SHORT Cycles per instruction
EVENTSET
PMC0 INSTRUCTIONS_EXECUTED
PMC1 CPU_CLK_UNHALTED
METRICS
Runtime (RDTSC) [s] time
Runtime unhalted [s] PMC1*inverseClock
CPI PMC1/PMC0
IPC PMC0/PMC1
LONG
Formulas:
CPI = CPU_CLK_UNHALTED/INSTRUCTIONS_EXECUTED
IPC = INSTRUCTIONS_EXECUTED/CPU_CLK_UNHALTED
-
This group measures how efficient the processor works with
regard to instruction throughput. Also important as a standalone
metric is INSTRUCTIONS_RETIRED as it tells you how many instruction
you need to execute for a task. An optimization might show very
low CPI values but execute many more instruction for it.