Re: [PATCH v7 07/20] perf record: Introduce data transferred and compressed stats

From: Bayduraev, Alexey V
Date: Wed Jun 30 2021 - 08:19:30 EST



Hi,

On 30.06.2021 11:05, Riccardo Mancini wrote:
> Hi,
>
> On Tue, 2021-06-22 at 11:42 +0300, Alexey Bayduraev wrote:
>> Introduce bytes_transferred and bytes_compressed stats so they
>> would capture statistics for the related data buffer transfers.
>>
>> Acked-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
>> Signed-off-by: Alexey Bayduraev <alexey.v.bayduraev@xxxxxxxxxxxxxxx>
>> ---
>>  tools/perf/builtin-record.c | 64 +++++++++++++++++++++++++++++--------
>>  tools/perf/util/mmap.h      |  3 ++
>>  2 files changed, 54 insertions(+), 13 deletions(-)
>>
>> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
>> index 38bb5afbb359..c9fd31211600 100644
>> --- a/tools/perf/builtin-record.c
>> +++ b/tools/perf/builtin-record.c
>> @@ -198,6 +198,11 @@ static int record__write(struct record *rec, struct mmap
>> *map __maybe_unused,
>>                 return -1;
>>         }
>>  
>> +       if (map && map->file) {
>> +               map->bytes_written += size;
>> +               return 0;
>> +       }
>> +
>>         rec->bytes_written += size;
>>  
>>         if (record__output_max_size_exceeded(rec) && !done) {
>
> This breaks the --max-size option in parallel trace mode.
> Maybe, we could change record__output_max_size_exceeded to check all
> thread_data->maps and sum up bytes_written. Concurrency should not be an issue
> since it's not required to stop at exactly the max-size (this is also the
> current behaviour).
> Otherwise, we could atomically increase an accumulator inside struct record
> (maybe rec->bytes_written could be reused, but I'm not sure if it's used by the
> main thread in the parallel mode), and check it for exceeded max size.

Thanks, currently threaded mode doesn't use rec->bytes_written and atomic64_t
framework is not available in kernel/tools.
I think better is to calculate sum of map->bytes_written like for threads
statistics.

Regards,
Alexey

>
> Thanks,
> Riccardo
>
>
>> @@ -215,8 +220,8 @@ static int record__write(struct record *rec, struct mmap
>> *map __maybe_unused,
>>  
>>  static int record__aio_enabled(struct record *rec);
>>  static int record__comp_enabled(struct record *rec);
>> -static size_t zstd_compress(struct perf_session *session, void *dst, size_t
>> dst_size,
>> -                           void *src, size_t src_size);
>> +static size_t zstd_compress(struct zstd_data *data,
>> +                           void *dst, size_t dst_size, void *src, size_t
>> src_size);
>>  
>>  #ifdef HAVE_AIO_SUPPORT
>>  static int record__aio_write(struct aiocb *cblock, int trace_fd,
>> @@ -350,9 +355,13 @@ static int record__aio_pushfn(struct mmap *map, void *to,
>> void *buf, size_t size
>>          */
>>  
>>         if (record__comp_enabled(aio->rec)) {
>> -               size = zstd_compress(aio->rec->session, aio->data + aio->size,
>> -                                    mmap__mmap_len(map) - aio->size,
>> +               struct zstd_data *zstd_data = &aio->rec->session->zstd_data;
>> +
>> +               aio->rec->session->bytes_transferred += size;
>> +               size = zstd_compress(zstd_data,
>> +                                    aio->data + aio->size,
>> mmap__mmap_len(map) - aio->size,
>>                                      buf, size);
>> +               aio->rec->session->bytes_compressed += size;
>>         } else {
>>                 memcpy(aio->data + aio->size, buf, size);
>>         }
>> @@ -577,8 +586,22 @@ static int record__pushfn(struct mmap *map, void *to,
>> void *bf, size_t size)
>>         struct record *rec = to;
>>  
>>         if (record__comp_enabled(rec)) {
>> -               size = zstd_compress(rec->session, map->data,
>> mmap__mmap_len(map), bf, size);
>> +               struct zstd_data *zstd_data = &rec->session->zstd_data;
>> +
>> +               if (map->file) {
>> +                       zstd_data = &map->zstd_data;
>> +                       map->bytes_transferred += size;
>> +               } else {
>> +                       rec->session->bytes_transferred += size;
>> +               }
>> +
>> +               size = zstd_compress(zstd_data, map->data,
>> mmap__mmap_len(map), bf, size);
>>                 bf   = map->data;
>> +
>> +               if (map->file)
>> +                       map->bytes_compressed += size;
>> +               else
>> +                       rec->session->bytes_compressed += size;
>>         }
>>  
>>         thread->samples++;
>> @@ -1311,18 +1334,15 @@ static size_t process_comp_header(void *record, size_t
>> increment)
>>         return size;
>>  }
>>  
>> -static size_t zstd_compress(struct perf_session *session, void *dst, size_t
>> dst_size,
>> +static size_t zstd_compress(struct zstd_data *zstd_data, void *dst, size_t
>> dst_size,
>>                             void *src, size_t src_size)
>>  {
>>         size_t compressed;
>>         size_t max_record_size = PERF_SAMPLE_MAX_SIZE - sizeof(struct
>> perf_record_compressed) - 1;
>>  
>> -       compressed = zstd_compress_stream_to_records(&session->zstd_data, dst,
>> dst_size, src, src_size,
>> +       compressed = zstd_compress_stream_to_records(zstd_data, dst, dst_size,
>> src, src_size,
>>                                                      max_record_size,
>> process_comp_header);
>>  
>> -       session->bytes_transferred += src_size;
>> -       session->bytes_compressed  += compressed;
>> -
>>         return compressed;
>>  }
>>  
>> @@ -2006,8 +2026,10 @@ static int record__start_threads(struct record *rec)
>>  
>>  static int record__stop_threads(struct record *rec, unsigned long *waking)
>>  {
>> -       int t;
>> +       int t, tm;
>> +       struct mmap *map, *overwrite_map;
>>         struct thread_data *thread_data = rec->thread_data;
>> +       u64 bytes_written = 0, bytes_transferred = 0, bytes_compressed = 0;
>>  
>>         for (t = 1; t < rec->nr_threads; t++)
>>                 record__terminate_thread(&thread_data[t]);
>> @@ -2015,9 +2037,25 @@ static int record__stop_threads(struct record *rec,
>> unsigned long *waking)
>>         for (t = 0; t < rec->nr_threads; t++) {
>>                 rec->samples += thread_data[t].samples;
>>                 *waking += thread_data[t].waking;
>> -               pr_debug("threads[%d]: samples=%lld, wakes=%ld,
>> trasferred=%ld, compressed=%ld\n",
>> +               for (tm = 0; tm < thread_data[t].nr_mmaps; tm++) {
>> +                       if (thread_data[t].maps) {
>> +                               map = thread_data[t].maps[tm];
>> +                               bytes_transferred += map->bytes_transferred;
>> +                               bytes_compressed += map->bytes_compressed;
>> +                               bytes_written += map->bytes_written;
>> +                       }
>> +                       if (thread_data[t].overwrite_maps) {
>> +                               overwrite_map =
>> thread_data[t].overwrite_maps[tm];
>> +                               bytes_transferred += overwrite_map-
>>> bytes_transferred;
>> +                               bytes_compressed += overwrite_map-
>>> bytes_compressed;
>> +                               bytes_written += overwrite_map->bytes_written;
>> +                       }
>> +               }
>> +               rec->session->bytes_transferred += bytes_transferred;
>> +               rec->session->bytes_compressed += bytes_compressed;
>> +               pr_debug("threads[%d]: samples=%lld, wakes=%ld,
>> trasferred=%ld, compressed=%ld, written=%ld\n",
>>                          thread_data[t].tid, thread_data[t].samples,
>> thread_data[t].waking,
>> -                        rec->session->bytes_transferred, rec->session-
>>> bytes_compressed);
>> +                        bytes_transferred, bytes_compressed, bytes_written);
>>         }
>>  
>>         return 0;
>> diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h
>> index c4aed6e89549..c04ca4b5adf5 100644
>> --- a/tools/perf/util/mmap.h
>> +++ b/tools/perf/util/mmap.h
>> @@ -46,6 +46,9 @@ struct mmap {
>>         int             comp_level;
>>         struct perf_data_file *file;
>>         struct zstd_data      zstd_data;
>> +       u64                   bytes_transferred;
>> +       u64                   bytes_compressed;
>> +       u64                   bytes_written;
>>  };
>>  
>>  struct mmap_params {
>
>