Low FPS in PointCloud2 visualization

[k0suke-murakami]

Bug report

Required Info:

• Operating System:
  • Ubuntu 20.04
• Installation type:
  • binary
• Version or commit hash:
  • Foxy
  • rviz2: 8.2.1-1focal.20210226.004041
• DDS implementation:
  • Fast-RTPS
• Client library (if applicable):
  • rclcpp

Steps to reproduce the issue

1. Clone my test repository
   a. git clone git@github.com:k0suke-murakami/send_lots_of_points_node_ros2.git
2. Clone pcl_perception
   a. git@github.com:ros-perception/perception_pcl.git
   b. git checkout foxy-devel
3. Build
4. Run
   a. rviz2 @Terminal1
   b. ros2 run send_lots_of_points_node_ros2 send_lots_of_points_node_ros2 1 200 1000 @terminal2

Expected behavior

Tested in ROS1(melodic) with similar code (https://github.com/k0suke-murakami/send_lots_of_points_node_ros1)
rosrun send_lots_of_points_node send_lots_of_points_node 1 200 1000
FPS is not low for visualizing 200*1000 points in ROS1. It is around 21FPS.

aasssa-2021-03-12_14.30.48.mp4

Actual behavior

FPS is almost 0.

simplescreenrecorder-2021-03-12_14.37.46.mp4

Additional information

[adamdbrw]

We are investigating this at the moment and have some idea why this might be happening