Re: [PATCH v10 09/12] perf record: implement -z,--compression_level[=<n>] option

[Alexey Budankov]

On 14.05.2019 23:04, Arnaldo Carvalho de Melo wrote:
> Em Mon, Mar 18, 2019 at 08:44:42PM +0300, Alexey Budankov escreveu:
>>
>> Implemented -z,--compression_level[=<n>] option that enables compression
>> of mmaped kernel data buffers content in runtime during perf record
>> mode collection. Default option value is 1 (fastest compression).
>>
>> Compression overhead has been measured for serial and AIO streaming
>> when profiling matrix multiplication workload:
>>
>>     -------------------------------------------------------------
>>     | SERIAL			  | AIO-1                       |
>> ----------------------------------------------------------------|
> 
> Please don't have lines starting with --- in the cset comment log
> message, breaks scripts, fixing it up now.

Oops, will do my best about that. Thanks.

~Alexey

> 
> - Arnaldo
> 
>> |-z | OVH(x) | ratio(x) size(MiB) | OVH(x) | ratio(x) size(MiB) |
>> |---------------------------------------------------------------|
>> | 0 | 1,00   | 1,000    179,424   | 1,00   | 1,000    187,527   |
>> | 1 | 1,04   | 8,427    181,148   | 1,01   | 8,474    188,562   |
>> | 2 | 1,07   | 8,055    186,953   | 1,03   | 7,912    191,773   |
>> | 3 | 1,04   | 8,283    181,908   | 1,03   | 8,220    191,078   |
>> | 5 | 1,09   | 8,101    187,705   | 1,05   | 7,780    190,065   |
>> | 8 | 1,05   | 9,217    179,191   | 1,12   | 6,111    193,024   |
>> -----------------------------------------------------------------
>>
>> OVH = (Execution time with -z N) / (Execution time with -z 0)
>>
>> ratio - compression ratio
>> size  - number of bytes that was compressed
>>
>> 	size ~= trace size x ratio
>>
>> Signed-off-by: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
>> ---
>>  tools/perf/Documentation/perf-record.txt |  5 +++++
>>  tools/perf/builtin-record.c              | 25 ++++++++++++++++++++++++
>>  2 files changed, 30 insertions(+)
>>
>> diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
>> index 18fceb49434e..0567bacc2ae6 100644
>> --- a/tools/perf/Documentation/perf-record.txt
>> +++ b/tools/perf/Documentation/perf-record.txt
>> @@ -471,6 +471,11 @@ Also at some cases executing less trace write syscalls with bigger data size can
>>  shorter than executing more trace write syscalls with smaller data size thus lowering
>>  runtime profiling overhead.
>>  
>> +-z::
>> +--compression-level[=n]::
>> +Produce compressed trace using specified level n (default: 1 - fastest compression,
>> +22 - smallest trace)
>> +
>>  --all-kernel::
>>  Configure all used events to run in kernel space.
>>  
>> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
>> index 2e083891affa..7258f2964a3b 100644
>> --- a/tools/perf/builtin-record.c
>> +++ b/tools/perf/builtin-record.c
>> @@ -440,6 +440,26 @@ static int record__mmap_flush_parse(const struct option *opt,
>>  	return 0;
>>  }
>>  
>> +#ifdef HAVE_ZSTD_SUPPORT
>> +static unsigned int comp_level_default = 1;
>> +static int record__parse_comp_level(const struct option *opt,
>> +				    const char *str,
>> +				    int unset)
>> +{
>> +	struct record_opts *opts = (struct record_opts *)opt->value;
>> +
>> +	if (unset) {
>> +		opts->comp_level = 0;
>> +	} else {
>> +		if (str)
>> +			opts->comp_level = strtol(str, NULL, 0);
>> +		if (!opts->comp_level)
>> +			opts->comp_level = comp_level_default;
>> +	}
>> +
>> +	return 0;
>> +}
>> +#endif
>>  static unsigned int comp_level_max = 22;
>>  
>>  static int record__comp_enabled(struct record *rec)
>> @@ -2169,6 +2189,11 @@ static struct option __record_options[] = {
>>  	OPT_CALLBACK(0, "affinity", &record.opts, "node|cpu",
>>  		     "Set affinity mask of trace reading thread to NUMA node cpu mask or cpu of processed mmap buffer",
>>  		     record__parse_affinity),
>> +#ifdef HAVE_ZSTD_SUPPORT
>> +	OPT_CALLBACK_OPTARG('z', "compression-level", &record.opts, &comp_level_default,
>> +		     "n", "Produce compressed trace using specified level (default: 1 - fastest compression, 22 - smallest trace)",
>> +		     record__parse_comp_level),
>> +#endif
>>  	OPT_END()
>>  };
>>  
>> -- 
>> 2.20.1
>