Some OProfile preferences can be set with a graphical interface. To
start it, execute the oprof_start command as root at
a shell prompt.
After changing any of the options, save them by clicking the
Save and quit button. The preferences are written
to /root/.oprofile/daemonrc, and the application
exits. Exiting the application does not stop OProfile from sampling.
On the Setup tab, to set events for the processor
counters as discussed in Section 41.2.2 Setting Events to Monitor, select the
counter from the pulldown menu and select the event from the list. A
brief description of the event appears in the text box below the
list. Only events available for the specific counter and the specific
architecture are displayed. The interface also displays whether the
profiler is running and some brief statistics about it.
On the right side of the tab, select the Profile
kernel option to count events in kernel mode for the
currently selected event, as discussed in Section 41.2.3 Separating Kernel and User-space Profiles. If
this option is unselected, no samples are collected for the kernel.
Select the Profile user binaries option to count
events in user mode for the currently selected event, as discussed in
Section 41.2.3 Separating Kernel and User-space Profiles. If this option is
unselected, no samples are collected for user applications.
Use the Count text field to set the sampling rate
for the currently selected event as discussed in Section 41.2.2.1 Sampling Rate.
If any unit masks are available for the currently selected event, as
discussed in Section 41.2.2.2 Unit Masks, they are
displayed in the Unit Masks area on the right side
of the Setup tab. Select the checkbox beside the
unit mask to enable it for the event.
On the Configuration tab, to profile the kernel,
enter the name and location of the vmlinux file for
the kernel to monitor in the Kernel image file text
field. To configure OProfile not to monitor the kernel, select
No kernel image.
If the Verbose option is selected, the
oprofiled daemon log includes more information.
If Per-application kernel samples files is
selected, OProfile generates per-application profiles for the kernel and
kernel modules as discussed in Section 41.2.3 Separating Kernel and User-space Profiles. This is equivalent to the
opcontrol --separate=kernel command. If
Per-application shared libs samples files is
selected, OProfile generates per-application profiles for
libraries. This is equivalent to the opcontrol
--separate=library command.
To force data to be written to samples files as discussed in Section 41.5 Analyzing the Data, click the Flush
profiler data button. This is equivalent to the
opcontrol --dump command.
To start OProfile from the graphical interface, click Start
profiler. To stop the profiler, click Stop
profiler. Exiting the application does not stop OProfile
from sampling.
