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perf_counter tools: Also display time-normalized stat results 

Add new column that normalizes counter results by
'nanoseconds spent running' unit.

Before:

 Performance counter stats for '/home/mingo/hackbench':

   10469.403605  task clock ticks     (msecs)
          75502  context switches     (events)
           9501  CPU migrations       (events)
          36158  pagefaults           (events)
    31975676185  CPU cycles           (events)
    26257738659  instructions         (events)
      108740581  cache references     (events)
       54606088  cache misses         (events)

 Wall-clock time elapsed:   810.514504 msecs

After:

 Performance counter stats for '/home/mingo/hackbench':

   10469.403605  task clock ticks     (msecs)
          75502  context switches     #        0.007 M/sec
           9501  CPU migrations       #        0.001 M/sec
          36158  pagefaults           #        0.003 M/sec
    31975676185  CPU cycles           #     3054.202 M/sec
    26257738659  instructions         #     2508.045 M/sec
      108740581  cache references     #       10.387 M/sec
       54606088  cache misses         #        5.216 M/sec

 Wall-clock time elapsed:   810.514504 msecs

The advantage of that column is that it is characteristic of the
execution workflow, regardless of runtime. Hence 'hackbench 10'
will look similar to 'hackbench 15' - while the absolute counter
values are very different.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ingo Molnar 2009-05-29 09:10:54 +02:00
parent 2996f5ddb7
commit be1ac0d81d
1 changed files with 11 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
Documentation/perf_counter/builtin-stat.c
View File

@ -74,6 +74,8 @@ static const unsigned int default_count[] = {
static __u64 event_res[MAX_COUNTERS][3];
static __u64 event_scaled[MAX_COUNTERS];
static __u64 runtime_nsecs;
static void create_perfstat_counter(int counter)
{
struct perf_counter_hw_event hw_event;
@ -165,6 +167,11 @@ static void read_counter(int counter)
((double)count[0] * count[1] / count[2] + 0.5);
}
}
/*
* Save the full runtime - to allow normalization during printout:
*/
if (event_id[counter] == EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK))
runtime_nsecs = count[0];
}
/*
@ -190,8 +197,11 @@ static void print_counter(int counter)
fprintf(stderr, " %14.6f %-20s (msecs)",
msecs, event_name(counter));
} else {
fprintf(stderr, " %14Ld %-20s (events)",
fprintf(stderr, " %14Ld %-20s",
count[0], event_name(counter));
if (runtime_nsecs)
fprintf(stderr, " # %12.3f M/sec",
(double)count[0]/runtime_nsecs*1000.0);
}
if (scaled)
fprintf(stderr, " (scaled from %.2f%%)",