perf stat: Analyze front-end and back-end stall counts
Sample output:
Performance counter stats for './loop_1b':
873.691065 task-clock # 1.000 CPUs utilized
1 context-switches # 0.000 M/sec
1 CPU-migrations # 0.000 M/sec
96 page-faults # 0.000 M/sec
2,012,637,222 cycles # 2.304 GHz (66.58%)
1,001,397,911 stalled-cycles-frontend # 49.76% frontend cycles idle (66.58%)
7,523,398 stalled-cycles-backend # 0.37% backend cycles idle (66.76%)
2,004,551,046 instructions # 1.00 insns per cycle
# 0.50 stalled cycles per insn (66.80%)
1,001,304,992 branches # 1146.063 M/sec (66.76%)
39,453 branch-misses # 0.00% of all branches (66.64%)
0.874046121 seconds time elapsed
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-7y40wib8n003io7hjpn1dsrm@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
d3d1e86da0