thread-caused malfunction

[DrShIkIgAmy]

Hi @Samahu , there're some critical issues in ros2 version (at least ros2 version) srcs.
Case: Since it is components, I'd like to run it under container. I have two lidars and I have to run two os_cloud_node and two os_sensor_node. To obtain resulting point cloud I have to run merger_component (custom component). Now here we got a problem: to provide effective intra-process comm I have to run all five nodes under one container, so it would be one process with several threads. At this point I face at least two problems. First one is: the sensor reinits continuously. The second one is: pointcloud messages could get corrupted.

ouster-ros/ouster-ros/src/os_sensor_node.cpp

Line 697 in 592e316

static uint32_t last_init_id = current_init_id + 1;

ouster-ros/ouster-ros/src/os_cloud_node.cpp

Line 177 in 592e316

static pcl::PCLPointCloud2 pcl_pc2;

The problem lays in the static vars. I can't even imaging what for u've used the static var in these cases, but it is big mistake.

[Samahu]

Hi @ DrShIkIgAmy, thanks for contacting us. I have not accounted for the cases when users run more than one component of the same type in the same process. In this case, static variables will cause issues. I will address this ASAP. Ussama

[DrShIkIgAmy]

I appreciate it. I thought that it's common to use at least two lidars on autonomous object, so the static vars look like a bug to me, so I tagged it like a bug. I don't know that it is not considered to run under one process. But I would be nice to implement that possibility, 'cause it could increase efficiency of node communication.

[Samahu]

@DrShIkIgAmy Could you try any of the two pull requests and check if this completely resolves the issue for your use case or not?

• ROS rolling/humble: SW-4859: enable having multiple components of same-type under same process #108
• ROS foxy: SW-4859: enable having multiple components of same type under same process #109

Thanks
Ussama

[Samahu]

@DrShIkIgAmy Any luck verifying that the changes included in #108 and #109 fully addresses this issue? I am ready to merge it but I don't want to do so right away and then find out that I missed something that still prevents you from spawning multiple components of same type within the same process.

[Samahu]

@DrShIkIgAmy I haven't heard back from you since last week, I did run my own assessment which includes setting up multiple sensors and cloud nodes within a single process. That being said I went ahead and merged the fix. Let me know if this didn't fully address your problem.