ROS performance test

This repository provides example files for testing and comparing ROS nodes written in python and C++.

• Tested on Indigo
• ROS node files are placed in src/ .
• Showing the results is done by running the plotter file in scripts/.

Nodes

• C++ publisher node publishes to topic test_msg_cpp
• Python publisher node publishes to topic test_msg_py
• C++ and Python subscriber nodes both listen to both of these topics

In total there are four different combinations

• C++ publisher to Python subscriber
• C++ publisher to C++ subscriber
• Python publisher to Python subscriber
• Python publisher to C++ subscriber

Method

• Everytime the callback of the subscriber is called, the current clock is recorded and compared to the previous clock call
• This comparison provides the loop rate on subscriber side and can be compared to the nominal publishing rate on publisher side
• In each subscriber, there is a counter to counter the number of calls to the callback function. Once this counter reaches COUNTER_MAX, all the recorded loop rates are written to a file in data_saved/ directory
• The comparison of these four combinations can be shown by running scripts/plot_results.py

Results

Three sample results for communication frequencies of 50 Hz, 1 kHz and 5 kHz are placed in data_saved/.

Run

• Both publisher nodes require a parameter called period. This parameter can be given via rosparam server or via YAML files.
• You can either run via rosrun or roslaunch which uses the launch file included in launch/ directory