When ros2 creates a new topic, the CPU usage is high

还没有人认领这个 Issue。

- Hardware description: N/A
- RTOS: Freertos
- Installation type: micro_ros_setup
- Version or commit hash: humble

Steps to reproduce the issue
1. Start micro_ros_agent through ros2 launch;
2. htop -p `pidof micro_ros_agent` to check the change of CPU usage
3. Publish a message through ros2 topic pub /avoidance_status std_msgs/msg/UInt8 "{data: 0}", and you will find that the CPU usage soars from 7% to 30%, and then falls back to a stable state of 7%;
4. Create a publishing topic through rclcpp, only create it once, send at 20hz frequency for 30s, stop for 3min, and then send again..., the CPU usage only changes when starting the node, and there is no fluctuation during the middle operation.

Is there any way to solve this problem? If the CPU is insufficient, the main controller will not be able to run.

通过 ros2 launch 启动 micro_ros_agent，使用 htop 监控其进程，并使用所示的 ros2 topic pub 命令创建 topic，以复现该报告。将 CPU 峰值与 rclcpp 发布的情况进行比较，并跟踪 micro_ros_agent 中的 topic 创建路径。确定原因且创建 topic 不再导致报告中所述的过高 CPU 使用率，即视为完成。

由索引模型根据 Issue 内容生成。