24 Hours of Autonomous Operations: 5 Critical Lessons from VoxYZ

We ran VoxYZ completely autonomous for 24 hours to stress-test our systems. Here's what we learned when humans stepped away.

1. Memory Leaks Surface Under Sustained Load

What happened: CPU usage climbed from 15% to 78% over 16 hours.

Root cause: Our text processing pipeline wasn't releasing tokenizer objects after each request.

Fix: Implemented explicit garbage collection after every 100 processed items.

import gc

if request_count % 100 == 0:
    gc.collect()

2. Database Connection Pools Need Aggressive Timeouts

What happened: Database connections hung for 45+ minutes during a brief network hiccup.

Fix: Reduced connection timeout from 30 seconds to 5 seconds and added retry logic.

database:
  connection_timeout: 5
  retry_attempts: 3
  retry_delay: 2

3. Error Cascades Aren't Always Obvious

What happened: A single malformed audio file crashed the entire processing queue for 3 hours.

Fix: Added input validation and circuit breakers:

• Validate file headers before processing
• Skip to next item after 3 consecutive failures
• Alert when skip rate exceeds 10%

4. Disk Space Monitoring Needs Predictive Alerts

What happened: Temp files filled the disk at 3 AM when no one was watching.

Current fix: Alert when disk usage hits 70% (was 90%)

Better fix: Track disk usage growth rate and predict when we'll hit capacity.

5. Health Checks Must Test Real Functionality

What happened: Health endpoint returned 200 OK while the core transcription service was down.

Fix: Health checks now verify:

• Database connectivity
• Model loading status
• Queue processing capability
• Available disk space > 20%

Next Steps

1. Week 1: Deploy connection pool fixes and improved health checks
2. Week 2: Add predictive disk monitoring
3. Week 3: Run 72-hour autonomous test

Key Takeaway

Autonomous operation exposed edge cases our regular monitoring missed. The failures weren't dramatic—they were slow, silent degradations that would have been invisible during normal business hours.