About tracing and profiling an application
You use tracing and profiling to debug and tune an application.
When you run an application, you can generate an execution trace file.
You use the trace file to create a profile of your application.
The profile shows you which functions and events were called by
which other functions and events, how often they were called, when
garbage collection occurred, when objects were created and destroyed,
and how long each activity took to complete. This information helps you
find errors in the application’s logic and identify areas that you
should rewrite to improve performance.
PBDebug tracing
You can also generate a simple text trace file without timer
values by checking Enable PBDebug Tracing in the System Options dialog
box.
For more about PBDebug, see Generating a
trace file without timing information.
When you can trace an
application
You can create a trace file when you run an application in the
PowerBuilder environment, and when you run an executable outside
PowerBuilder. For machine-code executable files, the trace file is
generated only if you check the Trace Information check box when you
build the executable.
When you run an application with tracing turned on, PowerBuilder
records a timer value in a data file every time a specific activity
occurs. You control when logging begins and ends and which activities
are recorded.
Creating profiles
After you have generated a trace file, you can create several
different profiles or views of the application by extracting different
types of information from the trace file.
PowerBuilder provides three profiling tools that create profiles
(views) of the application for you, but you can also create your own
analysis tools.
Using profiling to tune an
application
Examining the profiles generated by the profiling tools tells you
where the application is spending the most time. You can also find
routines that are being called too often, routines being called that you
did not expect to call, or routines that are not being called at all.
Follow these suggestions for tuning an application:
-
The database connection process is often slow. Although you
might not be able to speed this up, you might be able to enhance the
user’s perception of performance by moving the database connection
process to a different place in your application. -
Use profiling to tune algorithms. Algorithmic fixes will yield
greater performance enhancements than changing single lines of
code.Optimizing an inefficient function is not as effective as
removing unneeded calls to that function. -
Focus on optimizing the routines that are called most
often.If you cannot speed up a routine, consider adding some user
feedback, such as updating MicroHelp or displaying a progress
bar.