Troubleshooting: UdfDataRecorder: Queue has reached max size of 180840

📌 Problem

During import of a TrueView Cycle into LP360 (or when reviewing system logs), the following error may be observed:

UdfDataRecorder: Queue has reached max size of 180840

This message originates from the sensor during data collection and is surfaced during LP360 import for user visibility.

This error indicates that the sensor’s data recorder was unable to write incoming LiDAR and/or image data to storage fast enough. As a result, the internal recording queue reached its maximum capacity and began dropping data.

This condition is typically associated with high sustained data throughput scenarios (commonly seen in mobile mapping configurations), but may occur in any collection if system performance limits are exceeded.

🔍 Root Cause

The error is caused by a mismatch between the rate of incoming sensor data and the system’s ability to write that data to storage.

Common contributing factors include:

• Storage performance limitations (most common)
  • Improperly formatted or degraded UMS/storage media
  • Reduced sustained write speed
• Recording configuration
  • Writing directly to USB storage instead of internal storage
• High system load
  • Elevated CPU utilization during acquisition
  • Increased processing contention affecting write performance
• General I/O contention
  • Camera or subsystem delays
  • Concurrent system warnings in logs (e.g., delayed images, discarded packets)

✅ Probable Resolutions

Primary Resolutions (Recommended)

• Reformat the UMS / storage media
  • Resolves fragmentation and formatting-related performance degradation
• Use internal storage for collection
  • Avoid writing directly to USB during acquisition
  • Transfer data after the collection is complete
• Verify storage hardware health and performance
  • Ensure media meets required sustained write speeds

Secondary Mitigations (If Issue Persists)

If the issue continues after addressing storage and configuration:

• Reduce data collection rate
  • Lower PRR (Pulse Repetition Rate)
  • Reduce FOV where appropriate
  • Adjust camera trigger rate

📚 Additional Guidance

• Firmware updates
  • May improve overall system performance but are not a primary or known direct fix for this condition
• Log review
  • Check for accompanying warnings such as:
    • Image delays
    • Missing images
    • Discarded data packets

🔑Summary

This error is a data recording throughput condition caused by the system’s inability to write incoming data fast enough during collection. The most effective resolutions focus on ensuring high-performance storage and proper recording configuration, with parameter reduction used only as a fallback mitigation.

📬 Need Help?

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