Fix outdated perf profiler documentation

The event types should now be chosen in a structured way, not as
additional arguments. This is a hotfix for 4.5. A more comprehensive
documentation of the settings will follow in master.

Task-number: QTCREATORBUG-19321
Change-Id: I56670bd8d54fa8a62eb35951d86e4023a2a8c680
Reviewed-by: Kari Oikarinen <kari.oikarinen@qt.io>
Reviewed-by: Eike Ziller <eike.ziller@qt.io>
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>
This commit is contained in:
Ulf Hermann
2017-11-21 14:52:00 +01:00
parent 194bde265c
commit 14db426133

View File

@@ -350,15 +350,14 @@
performance counters are dysfunctional and the Linux kernel may performance counters are dysfunctional and the Linux kernel may
randomly fail to record data after some time. Perf can use different randomly fail to record data after some time. Perf can use different
types of events to trigger samples. You can get a list of available types of events to trigger samples. You can get a list of available
event types by running \c {perf list} on the device and add event types by running \c {perf list} on the device and then choose
\c {-e <event type>} to the \uicontrol {Additional arguments} field the respective event types in the settings. The choice of event type
to change the event type to be used. The choice of event type affects the performance and stability of the sampling. The
affects the performance and stability of the sampling. \c {cpu-clock} \c {software} event is a safe but relatively slow
\c {-e cpu-clock} is a safe but relatively slow option as it option as it does not use the hardware performance counters, but
does not use the hardware performance counters, but drives the drives the sampling from software. After the sampling has failed,
sampling from software. After the sampling has failed, reboot the reboot the device. The kernel may have disabled important parts of
device. The kernel may have disabled important parts of the the performance counters system.
performance counters system.
\endlist \endlist
Output from the helper program that processes the data is displayed in the Output from the helper program that processes the data is displayed in the