Re: [PATCH 00/10] perf tools: Use SIGUSR2 control data dumpping

["Wangnan (F)" <wangnan0@huawei.com>]

On 2016/4/15 18:40, Jiri Olsa wrote:
> On Wed, Apr 13, 2016 at 08:21:03AM +0000, Wang Nan wrote:
>> This patch set is a preparation to support overwritable ring buffer.
>> However, even without the kernel side core patch [1] is accept this
>> patch set is still useful.
>>
>> With this patch set, perf switches output when receiving SIGUSR2. For
>> example:
>>
>>   # perf record -a -F99 --switch-output &
>>   [1] 26435
>>   # kill -s SIGUSR2 26435
>>   [ perf record: dump data: Woken up 1 times ]
>>   # [ perf record: Dump perf.data.2016041323544373 ]
>>   # kill -s SIGUSR2 26435
>>   [ perf record: dump data: Woken up 1 times ]
>>   # [ perf record: Dump perf.data.2016041323544730 ]
>>   # fg
>>   perf record -a -F99 --switch-output
>>   ^C[ perf record: Woken up 1 times to write data ]
>>   [ perf record: Dump perf.data.2016041323545019 ]
>>   [ perf record: Captured and wrote 0.395 MB perf.data.<timestamp> ]
>>
>> User can periodically generates perf trace with a simple script, then
>> remove most of them, only keeps scripts collected when something
>> unusual is detected.
>>
>> After [1], perf can be totally silent before receiving SIGUSR2. Trace
>> is collected in kernel overwritable ring buffer, and dumpped when
>> SIGUSR2 is received.
>>
>> [1] http://lkml.kernel.org/r/1459865478-53413-1-git-send-email-wangnan0@huawei.com
>>
>> Cc: Wang Nan <wangnan0@huawei.com>
>> Cc: He Kuang <hekuang@huawei.com>
>> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
>> Cc: Jiri Olsa <jolsa@kernel.org>
>> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
>> Cc: Namhyung Kim <namhyung@kernel.org>
>> Cc: Zefan Li <lizefan@huawei.com>
>> Cc: pi3orama@163.com
>>
>> Wang Nan (10):
>>    perf tools: Make ordered_events reusable
>>    perf tools: Add perf_data_file__switch() helper
>>    perf record: Turns auxtrace_snapshot_enable into 3 states
>>    perf record: Add '--timestamp-filename' option to append timestamp to
>>      output filename
>>    perf record: Split output into multiple files via '--switch-output'
>>    perf record: Force enable --timestamp-filename when --switch-output is
>>      provided
>>    perf record: Disable buildid cache options by default in switch output
>>      mode
>>    perf record: Re-synthesize tracking events after output switching
>>    perf record: Generate tracking events for process forked by perf
>>    perf core: Add backward attribute to perf event
> I did not get 3/10 patch and the patchset did not apply cleanly,
> git am failed.. would you have it in a branch somewhere?

Sorry, you are not in the CC list. 'git send-email' failed to extract your
email address from the Acked-by tag.

I'll inform you after I putting them into a git branch. Please wait.

Thank you.