mirror of
https://github.com/ClusterCockpit/cc-metric-collector.git
synced 2024-11-14 05:57:25 +01:00
24 lines
797 B
Plaintext
24 lines
797 B
Plaintext
|
SHORT L1 TLB misses
|
||
|
|
|
||
|
|
EVENTSET
|
||
|
|
PMC0 DATA_PAGE_WALK
|
||
|
|
PMC1 DATA_READ_OR_WRITE
|
||
|
|
|
||
|
|
METRICS
|
||
|
|
Runtime (RDTSC) [s] time
|
||
|
|
L1 TLB misses [misses/s] PMC0/time
|
||
|
|
L1 TLB miss ratio PMC0/PMC1
|
||
|
|
|
||
|
|
LONG
|
||
|
|
Formulas:
|
||
|
|
L1 TLB misses [misses/s] = DATA_PAGE_WALK/time
|
||
|
|
L1 TLB miss ratio = DATA_PAGE_WALK/DATA_READ_OR_WRITE
|
||
|
|
-
|
||
|
|
This performance group measures the L1 TLB misses. A L1 TLB miss that hits the
|
||
|
|
L2 TLB has a penelty of about 25 cycles for 4kB pages. For 2MB pages, the penelty
|
||
|
|
for a L1 TLB miss that hits L2 TLB is about 8 cycles. The minimal L1 TLB miss ratio
|
||
|
|
is about 1/64, so a high ratio indicates a bad spartial locality. Data of a page
|
||
|
|
is only partly accessed. It can also indicate trashing because when multiple pages
|
||
|
|
are accessed in a loop iteration, the size and associativity is not sufficient to
|
||
|
|
hold all pages.
|