Developer Guide

  • 2021.1
  • 11/03/2021
  • Public
Contents

Monitor Measurements Only

You can run the measurement analysis sample to monitor latency measurements collected from a real-time application during application run. The real-time application must be instrumented with measurement library APIs.
In this mode, the analysis sample runs the instrumented application, attaches to the shared memory buffer, and starts reading the latency data that the instrumented application placed there. The sample prints each latency measurement. After the application is finished, the analysis sample also stops. This type of analysis is called “online” monitoring. This means that the results are constantly read from the shared memory buffer where they are placed by the instrumented application.
The analysis sample monitors the specified measurement instances from the real-time application. A
measurement instance
refers to the measurement library APIs that you have added to your application to measure the latency of the real-time cycle or any part of it. For more information about instrumenting your code with measurement library APIs, see Instrument the Code.
The following example monitors data collected from the multiple measurements sample (
tcc_multiple_measurements_sample
).
To run this example:
  1. From your host system, connect to the target system:
    ssh <user>@<target>
  2. In the SSH session
    , run the sample. Both
    tcc_measurement_analysis_sample
    and
    tcc_multiple_measurements_sample
    are located in the system paths, so you can run the command from any directory:
    tcc_measurement_analysis_sample monitor "Multiplication:10" -time-units us -- tcc_multiple_measurements_sample --approximation 10000 --multiplication 100 --iterations 5
where:
Argument
Description
Multiplication:10
This argument specifies the measurement instance to collect:
  • “Multiplication” is the measurement name defined in the
    __itt_string_handle_create
    call in the
    tcc_multiple_measurements_sample
    .
  • “10” is the maximum number of measurements that can be stored for this measurement instance.
This argument has the same format as the
TCC_MEASUREMENTS_BUFFERS
environment variable. See Control Data Collection.
-time-units us
The output will display results in microseconds.
--
Separates the measurement analysis sample command from the real-time application command. For more information about the command-line options of
tcc_multiple_measurements_sample
, see Command-Line Options.
Example Output
The sample prints the output of the profiled application and the profiling results.
The profiling output includes the following:
  • Table of all measurement results. Each row represents one measured value.
  • Summary for each measurement instance:
    • Count of read data: Number of measurements that the analysis sample read from the shared memory buffer
MONITORING OUTPUT: ---------------------------------- Name Latency(us) ---------------------------------- Multiplication 3341 Multiplication 3251 Multiplication 3186 Multiplication 3192 Multiplication 3173 [Multiplication] Count of read data: 5 ------------------------------ APPLICATION OUTPUT: Running with arguments: approximation = 10000, multiplication = 100, iterations = 5 Running workloads. This may take a while, depending on iteration values. Workloads were run successfully.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.