perf(velodyne): remove mtqueue

[mojomex]

PR Type

• Improvement
• Bug fix

Related Links

• perf(hesai): remove decoder thread and MtQueue, make everything single-threaded #226 -- Hesai for reference
• test(nebula_ros): add smoke tests #240 -- smoke tests for reference

Description

Does what the title says.

Reasons for this change:

• The multithreaded queue is not needed (receive buffers in the network stack take care of arriving data while decoding).
• The decoder thread had no mechanism for gracefully stopping, thus causing an exception on exit
• The above excption caused our smoke tests to fail

Review Procedure

• Compare to the linked Hesai reference PR perf(hesai): remove decoder thread and MtQueue, make everything single-threaded #226
• Test with launch_hw:=false and a rosbag
• Test with launch_hw:=true and a real sensor or pcap

Pre-Review Checklist for the PR Author

PR Author should check the checkboxes below when creating the PR.

• Assign PR to reviewer

Checklist for the PR Reviewer

Reviewers should check the checkboxes below before approval.

• Commits are properly organized and messages are according to the guideline
• (Optional) Unit tests have been written for new behavior
• PR title describes the changes

Post-Review Checklist for the PR Author

PR Author should check the checkboxes below before merging.

• All open points are addressed and tracked via issues or tickets

CI Checks

• Build and test for PR: Required to pass before the merge.

[codecov]

Codecov Report

Attention: Patch coverage is 33.33333% with 2 lines in your changes missing coverage. Please review.

Project coverage is 28.16%. Comparing base (39fbbe7) to head (2b367c2).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #276      +/-   ##
==========================================
- Coverage   30.23%   28.16%   -2.07%     
==========================================
  Files         112      112              
  Lines        9695     9479     -216     
  Branches     3652     2918     -734     
==========================================
- Hits         2931     2670     -261     
- Misses       6224     6347     +123     
+ Partials      540      462      -78     

Flag	Coverage Δ
differential	28.16% <33.33%> (?)
total	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
Common	18.37% <ø> (-31.87%)	⬇️
Hesai	29.69% <ø> (-0.72%)	⬇️
Velodyne	40.42% <33.33%> (+2.76%)	⬆️
Continental	28.06% <ø> (+0.07%)	⬆️
Robosense	0.00% <ø> (ø)

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[mojomex]

🟢 Self-Evaluation

Tested on a VLS128 rosbag and on a real VLP16 device, there were no packet drops/framerate drops/high CPU load etc.