lkml.org 
[lkml]   [2009]   [Nov]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
Subjectperf stat output
Hi all!

Some questions about perf stat output. See example:


lucas@LMS-linux:~/programming/testprograms> perf stat -e
L1-dcache-loads -e L1-dcache-load-misses -- make -j
gcc test_schedchanges.c -o test_schedchanges
gcc -pthread test_taskaff1.c -o test_taskaff1
gcc -pthread test_taskaff2.c -o test_taskaff2
gcc -pthread test_taskaff3.c -o test_taskaff3

Performance counter stats for 'make -j':

161384667 L1-dcache-loads # 0.000 M/sec
24853791 L1-dcache-load-misses # 0.000 M/sec

0.066893389 seconds time elapsed

Why do we have both L1-dcache-loads and L1-dcache-load-misses with
0.000 M/sec? Also, why do we have 0 M/s when running "perf stat -a -e
cache-misses -e cache-references" but values different than 0 when
running "perf stat -a" without selecting the events?

The last question: what does the "scaled from X%" mean? Is it related
to the maximum number of performance registers a processor can count
at a time?


Thanks

Lucas De Marchi


\
 
 \ /
  Last update: 2009-11-12 23:05    [W:0.059 / U:0.200 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site