Intel IXP400 manual Display Xcycle Measurement

Intel® IXP400 Software

Access-Layer Components: Performance Profiling (IxPerfProfAcc) API

This pointer is interpreted as “the number of 66-MHz clock ticks for one measurement.” It is stored within the tool while it is being run and serves only as a reference for the user.

2.Create a thread that runs the code to be monitored. To begin the Xcycle measurements, call the start function, with parameter:

ixPerfProfAccXcycleStart(UINT32 numMeasurementsRequested)

This start the measurements immediately. numMeasurementsRequested specifies number of measurements to run.

If numMeasurementsRequested is set to 0, the measurement will be performed continuously until IxPerfProfAccXcycleStop() is called. It is estimated that one measurement takes approximately 1 s during low CPU utilization, therefore 128 measurement takes approximately 128 s.

When CPU utilization is high, the measurement will take longer. This function spawn a task the perform the measurement and returns. The measurement may continue even if this function returns.

There are only IX_PERFPROF_ACC_XCYCLE_MAX_NUM_OF_MEASUREMENTS storage available so storing is wrapped around if measurements are more than

IX_PERFPROF_ACC_XCYCLE_MAX_NUM_OF_MEASUREMENTS.

3.If ixPerfProfAccXcycleStart() is called with an input of zero, this indicates continuous measurements. In this case, the measurements are stopped, by calling the stop function:

ixPerfProfAccXcycleStop(void)

As it takes the measurements some time to complete, the user should call the following function to determine if any measurements are still running:

ixPerfProfAccXcycleInProgress(void)

4.To obtain the results of the measurements made, the user should call the results function, with parameter:

ixPerfProfAccXcycleResultsGet(IxPerfProfAccXcycleResults *xcycleResult)

The result contains:

—float maxIdlePercentage — Maximum percentage of Idle cycles

—float minIdlePercentage — Minimum percentage of Idle cycles

—float aveIdlePercentage — Average percentage of Idle cycles

—UINT32 totalMeasurements — Total number of measurement made

If the user has declared a pointer IxPerfProfAccXcycleResults *xcycleResult, the user may then print out the results of the xcycle measurements as shown in Figure 88.

Figure 88. Display Xcycle Measurement

printf("Maximum percentage of idle cycles = %f\n", xcycleResult->maxIdlePercentage); printf("Minimum percentage of idle cycles = %f\n", xcycleResult->minIdlePercentage); printf("Average percentage of idle cycles = %f\n", xcycleResult->aveIdlePercentage); printf("Total number of measurements = %u\n", xcycleResult->totalMeasurements);

April 2005	IXP400 Software Version 2.0	Programmer’s Guide
264	Document Number: 252539, Revision: 007