rttest

Instrumentation library for real-time performance testing

• C++ API
  • Class Hierarchy
  • File Hierarchy
  • Full C++ API
• Standard Documents
  • CHANGELOG
  • CONTRIBUTING
  • LICENSE
  • PACKAGE
  • README

README

rttest

rttest is a minimal tool for instrumenting and running tests for synchronous real-time systems. It provides utilities for measuring and plotting jitter, latency, and missed deadlines. It also provides a library with macros for instrumenting code. It is designed with real-time Linux-based systems in mind, such as Preempt RT kernel.

Build instructions

Build from source:

mkdir build
cd build

cmake ..
sudo make install

Alternatively for a local install:

cmake .. -DCMAKE_INSTALL_PREFIX=<build folder>
make install

Build and run the example:

cd examples
mkdir build
cd build
cmake .. (-DCMAKE_INSTALL_PREFIX=<build folder>)
make
./example_loop

Note that if this is run in a Docker container, the IPC_LOCK capability must be added to the container capabilities. This can be managed via the --cap-add flag:

docker run --cap-add IPC_LOCK

Command line arguments

Passing argc and argv of an instrumented main function to rttest_read_args will enable command line arguments for the instrumented function.

-u Specify the update period. Default units are microseconds. Use the suffix “s” for seconds, “ms” for milliseconds, “us” for microseconds, and “ns” for nanoseconds. Default update period is 1ms.

-m Set maximum stack prefault size for static stack prefaulting. “b” for bytes, “kb” for kilobytes, “mb” for megabytes, “gb” for gigabytes (use with caution). Default stack size is 1MB.

-d Set maximum heap prefault size for dynamic memory prefaulting. “b” for bytes, “kb” for kilobytes, “mb” for megabytes, “gb” for gigabytes (use with caution). Default heap size is 8192MB.

-i Specify how many iterations to run the real-time loop. Specifying an iteration value less than or equal to 0 will cause rttest to run forever or until interrupted with Ctrl-C. If running forever, rttest will not save a data buffer and writing results to a file will not work. Default value is 1000.

-tp Set the thread priority of all threads launched by the test program. Individual thread priority can be set using the rttest_set_sched_priority command.

-f Specify the name of the file for writing the collected data. Plot this data file using the rttest_plot script provided in scripts.