Activating the Performance Trace 

Use

Activate the performance trace if duration information for actions is to be written, where actions are comparable to the transaction steps of an SAP System. If, for example, the Global Workload Monitor shows that the average response time of an application is too high, you should activate the trace to find the cause.

Unlike the statistics, the performance trace has the advantage that the J2EE Engine appears transparent and the process durations for the individual modules of the Engine can be measured. This means that the trace provides a finer view of the processes in the J2EE Engine (see Performance Trace Recordings).

 

Procedure

The performance trace can be activated using the Visual Administrator of the J2EE Engine, from the command line, or by setting the TraceFlag indicator of an external passport.

 

Activating the Trace Using the Visual Administrator

You can start the trace using the DSR service in the Visual Administrator. To do this, follow the procedure below:

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       1.      Start Visual Administrator.

       2.      Choose Performance Tracing Service  →  Runtime  →  Trace Config.

A tab page with the following J2EE Engine modules appears:

○       JDBI (SQL) Trace

○       SAT Trigger

       3.      Use the radio buttons next to the modules to activate or deactivate the performance trace to set a user filter if required.

In the User column, you can enter a user name for each trace module for which trace data is to be collected. Otherwise, the trace is written for all users.

       4.      Save your entries.

 

Activating the Trace Using the Console

You can activate the performance trace using the console.  To do this, you must include the command group dsr with the command add dsr. The command group makes various shell commands available to you:

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       1.      You can use the command trace -state to query the trace status. The system displays the modules together with information about whether the trace is activated or deactivated for the individual modules, and which filters are set, if appropriate.

       2.      You can use the command trace -on -modules "x" "y" to set the trace for specific modules. The command trace -on -modules "<module_name1>" "<module_name2>" activates the performance trace for the modules with names <module_name1> and <module_name2> , correspondingly.

       3.      The command trace -user Smith -modules "<module_name>" creates a filter for the module with name <module_name> for the user Smith.

In the current command shell, you cannot set a user filter and activate or deactivate the performance trace at the same time. For example, the input trace -on -user Smith -modules "<module_name>" is not allowed.

 

Activating the Performance Trace Using the Passport

The passport contains the TraceFlag indicator, with which you can set the performance trace. So that there are not misunderstandings between the trace settings in the performance tracing service and the TraceFlag indicator, the system differentiates between a passport that was created within the J2EE Engine and one that was forwarded to the J2EE Engine from another component:

 

●      If the passport is created within the J2EE Engine, the TraceFlag indicator is not evaluated. The trace settings of the performance tracing service apply.

●      However, if the passport is taken on from another component, it has a control priority ahead of the settings of the Engine, and the TraceFlag indicator is taken into account. If the indicator in the passport is set externally, the performance tracing service of the J2EE Engine sets the trace for all modules simultaneously, as the indicator does not contain any information about the individual modules.

If the indicator is set in an external passport, the trace only remains active for the duration of the request. If you want to activate the trace over multiple requests, you must reset the indicator in the passport for each call.

Result

You have activated the performance trace. For more information, see Performance Trace Recordings

More Information

You can use the functional trace (transaction STATTRACE) to display performance traces in the central monitoring system. For more information, see Functional Trace