On Mon, Oct 21, 2019 at 07:51:17PM +0800, Jiwei Sun wrote: > Hello Arnaldo & Jirka, > > Do you have any other suggestions regarding the patch? > Any suggestions are welcome. Thank you very much.
oops, overlooked this one, sry.. I'll check on it today jirka > > Regards, > Jiwei > > On 2019e9409f 25f% 15:06, Jiwei Sun wrote: > > The patch adds a new option to limit the output file size, then based > > on it, we can create a wrapper of the perf command that uses the option > > to avoid exhausting the disk space by the unconscious user. > > > > In order to make the perf.data parsable, we just limit the sample data > > size, since the perf.data consists of many headers and sample data and > > other data, the actual size of the recorded file will bigger than the > > setting value. > > > > Testing it: > > > > # ./perf record -a -g --max-size=10M > > Couldn't synthesize bpf events. > > WARNING: The perf data has already reached the limit, stop recording! > > [ perf record: Woken up 30 times to write data ] > > [ perf record: Captured and wrote 10.233 MB perf.data (175650 samples) ] > > Terminated > > > > # ls -lh perf.data > > -rw------- 1 root root 11M Jul 17 14:01 perf.data > > > > # ./perf record -a -g --max-size=10K > > WARNING: The perf data has already reached the limit, stop recording! > > Couldn't synthesize bpf events. > > [ perf record: Woken up 0 times to write data ] > > [ perf record: Captured and wrote 1.824 MB perf.data (67 samples) ] > > Terminated > > > > # ls -lh perf.data > > -rw------- 1 root root 1.9M Jul 17 14:05 perf.data > > > > Signed-off-by: Jiwei Sun <[email protected]> > > --- > > v4 changes: > > - Just show one WARNING message after reached the limit. > > > > v3 changes: > > - add a test result > > - add the new option to tools/perf/Documentation/perf-record.txt > > > > v2 changes: > > - make patch based on latest Arnaldo's perf/core, > > - display warning message when reached the limit. > > --- > > tools/perf/Documentation/perf-record.txt | 4 +++ > > tools/perf/builtin-record.c | 42 ++++++++++++++++++++++++ > > 2 files changed, 46 insertions(+) > > > > diff --git a/tools/perf/Documentation/perf-record.txt > > b/tools/perf/Documentation/perf-record.txt > > index c6f9f31b6039..f1c6113fbc82 100644 > > --- a/tools/perf/Documentation/perf-record.txt > > +++ b/tools/perf/Documentation/perf-record.txt > > @@ -571,6 +571,10 @@ config terms. For example: 'cycles/overwrite/' and > > 'instructions/no-overwrite/'. > > > > Implies --tail-synthesize. > > > > +--max-size=<size>:: > > +Limit the sample data max size, <size> is expected to be a number with > > +appended unit character - B/K/M/G > > + > > SEE ALSO > > -------- > > linkperf:perf-stat[1], linkperf:perf-list[1] > > diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c > > index 48600c90cc7e..30904d2a3407 100644 > > --- a/tools/perf/builtin-record.c > > +++ b/tools/perf/builtin-record.c > > @@ -91,6 +91,7 @@ struct record { > > struct switch_output switch_output; > > unsigned long long samples; > > cpu_set_t affinity_mask; > > + unsigned long output_max_size; /* = 0: unlimited */ > > }; > > > > static volatile int auxtrace_record__snapshot_started; > > @@ -120,6 +121,12 @@ static bool switch_output_time(struct record *rec) > > trigger_is_ready(&switch_output_trigger); > > } > > > > +static bool record__output_max_size_exceeded(struct record *rec) > > +{ > > + return rec->output_max_size && > > + (rec->bytes_written >= rec->output_max_size); > > +} > > + > > static int record__write(struct record *rec, struct mmap *map > > __maybe_unused, > > void *bf, size_t size) > > { > > @@ -132,6 +139,12 @@ static int record__write(struct record *rec, struct > > mmap *map __maybe_unused, > > > > rec->bytes_written += size; > > > > + if (record__output_max_size_exceeded(rec)) { > > + WARN_ONCE(1, "WARNING: The perf data has already reached " > > + "the limit, stop recording!\n"); > > + raise(SIGTERM); > > + } > > + > > if (switch_output_size(rec)) > > trigger_hit(&switch_output_trigger); > > > > @@ -1936,6 +1949,33 @@ static int record__parse_affinity(const struct > > option *opt, const char *str, int > > return 0; > > } > > > > +static int parse_output_max_size(const struct option *opt, > > + const char *str, int unset) > > +{ > > + unsigned long *s = (unsigned long *)opt->value; > > + static struct parse_tag tags_size[] = { > > + { .tag = 'B', .mult = 1 }, > > + { .tag = 'K', .mult = 1 << 10 }, > > + { .tag = 'M', .mult = 1 << 20 }, > > + { .tag = 'G', .mult = 1 << 30 }, > > + { .tag = 0 }, > > + }; > > + unsigned long val; > > + > > + if (unset) { > > + *s = 0; > > + return 0; > > + } > > + > > + val = parse_tag_value(str, tags_size); > > + if (val != (unsigned long) -1) { > > + *s = val; > > + return 0; > > + } > > + > > + return -1; > > +} > > + > > static int record__parse_mmap_pages(const struct option *opt, > > const char *str, > > int unset __maybe_unused) > > @@ -2262,6 +2302,8 @@ static struct option __record_options[] = { > > "n", "Compressed records using specified level > > (default: 1 - fastest compression, 22 - greatest compression)", > > record__parse_comp_level), > > #endif > > + OPT_CALLBACK(0, "max-size", &record.output_max_size, > > + "size", "Limit the maximum size of the output file", > > parse_output_max_size), > > OPT_END() > > }; > > > >
