Performance

I am not an expert on profiling code. Even though better_launch uses synchronous calls (or classic threads if necessary), and does some additional work to reformat output from nodes, it was able to achieve similar performance to ros2 launch. The scripts and results from the benchmarks can be found under benchmarks. This section will only show the most relevant parts.

Note

bl is just a script to locate the launch file and then run it, so I decided to not use bl for these benchmarks and instead run the launch file directly; otherwise the resources used by the launch file will not be visible to most profilers.

memray

memray reports that better_launch uses about 30% less memory than ros2 launch.

	better_launch	ros2 launch
allocations	48196	60943
peak memory usage	6.6 MiB	9.7 MiB
details	link	link

psutil

psutil shows that better_launch uses more CPU in the beginning and more memory in total compared to ros2 launch. The memory reported is the unique set size (see the previous link). I'm not sure how these results relate to the memray statistics above.

py-spy

I use py-spy to see where better_launch is using resources that can still be optimized. The speedscope files can be visualized on speedscope.app.