1
linux/tools
Ingo Molnar 1fc570ad89 perf stat: Add stalled cycles to the default output
The new default output looks like this:

 Performance counter stats for './loop_1b_instructions':

        236.010686 task-clock               #    0.996 CPUs utilized
                 0 context-switches         #    0.000 M/sec
                 0 CPU-migrations           #    0.000 M/sec
                99 page-faults              #    0.000 M/sec
       756,487,646 cycles                   #    3.205 GHz
       354,938,996 stalled-cycles           #   46.92% of all cycles are idle
     1,001,403,797 instructions             #    1.32  insns per cycle
                                            #    0.35  stalled cycles per insn
       100,279,773 branches                 #  424.895 M/sec
            12,646 branch-misses            #    0.013 % of all branches

        0.236902540  seconds time elapsed

We dropped cache-refs and cache-misses and added stalled-cycles - this is a
more generic "how well utilized is the CPU" metric.

If the stalled-cycles ratio is too high then more specific measurements can be
taken to figure out the source of the inefficiency.

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-pbpl2l4mn797s69bclfpwkwn@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26 20:04:57 +02:00
..
firewire tools/firewire: nosy-dump: increment program version 2010-07-27 11:04:12 +02:00
perf perf stat: Add stalled cycles to the default output 2011-04-26 20:04:57 +02:00
power/x86 Fix common misspellings 2011-03-31 11:26:23 -03:00
slub slub: move slabinfo.c to tools/slub/slabinfo.c 2010-11-06 09:04:32 +02:00
testing/ktest Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-ktest 2011-03-21 14:13:48 -07:00
usb USB: ffs-test: fix header path 2011-02-28 19:27:12 -08:00
virtio tools/virtio: virtio_test tool 2010-12-09 16:00:22 +02:00