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| author | Namhyung Kim <namhyung.kim@lge.com> | 2013-01-08 13:39:26 +0400 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2013-01-24 23:40:19 +0400 |
| commit | 9b494ea2f5638184bc203a30062b32b9a9a05d9e (patch) | |
| tree | 0ddbaa8913c7ae232a938f39bed3abd00bb0bb83 /tools | |
| parent | eec185ab603fab3b7b5021e840cf4b282c4c7e6b (diff) | |
| download | linux-9b494ea2f5638184bc203a30062b32b9a9a05d9e.tar.xz | |
perf bench: Flush stdout before starting bench suite
perf bench prints header message for bench suite before starting the
benchmark. However if the stdout is redirected to a file and bench
suite forks child processes this (and possibly other debugging
messages too) will be repeated multiple times.
$ perf bench sched messaging
# Running sched/messaging benchmark...
# 20 sender and receiver processes per group
# 10 groups == 400 processes run
Total time: 0.100 [sec]
$ perf bench sched messaging > result.txt
$ wc -l result.txt
391
In this file, there were so many "Running sched/messaging benchmark..."
lines. This was because stdout is converted to fully-buffered due to
the redirection and inherited child processes. Other lines are printed
after reaping all those tasks.
So fix it by flushing stdout before starting bench suites.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Hitoshi Mitake <h.mitake@gmail.com>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1357637966-8216-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/perf/builtin-bench.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/tools/perf/builtin-bench.c b/tools/perf/builtin-bench.c index cae9a5fd2ecf..afd1255a632f 100644 --- a/tools/perf/builtin-bench.c +++ b/tools/perf/builtin-bench.c @@ -159,6 +159,7 @@ static void all_suite(struct bench_subsys *subsys) /* FROM HERE */ printf("# Running %s/%s benchmark...\n", subsys->name, suites[i].name); + fflush(stdout); argv[1] = suites[i].name; suites[i].fn(1, argv, NULL); @@ -225,6 +226,7 @@ int cmd_bench(int argc, const char **argv, const char *prefix __maybe_unused) printf("# Running %s/%s benchmark...\n", subsystems[i].name, subsystems[i].suites[j].name); + fflush(stdout); status = subsystems[i].suites[j].fn(argc - 1, argv + 1, prefix); goto end; |