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-wangn...@huawei.com
Cc: Wang Nan <wangn...@huawei.com>
Cc: He Kuang <heku...@huawei.com>
Cc: Arnaldo Carvalho de Melo <a...@redhat.com>
Cc: Jiri Olsa <jo...@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu...@hitachi.com>
Cc: Namhyung Kim <namhy...@kernel.org>
Cc: Zefan Li <lize...@huawei.com>
Cc: pi3or...@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.
