If your sync queue has stopped processing or items are stuck, follow this guide to get things moving again.

Symptoms

• Items stuck in queue for extended periods
• Queue count not decreasing
• Sync progress bar not moving
• Backlog continuously growing

Common Causes

1. WP-Cron Not Firing

WordPress's built-in cron is visitor-dependent and often fails on low-traffic sites.

Solution: Set up a server-side cron job for reliable, scheduled execution.

→ Server-Side Cron Setup Guide

2. Server Timeouts

Long-running sync operations may be killed by server timeout limits.

Symptoms:

• Partial syncs completing
• Items failing repeatedly
• Timeout errors in logs

Solutions:

• Increase max_execution_time in PHP settings
• Enable performance settings to reduce load
• Contact your host about increasing limits

3. Memory Limits

PHP memory exhaustion can stop queue processing.

Symptoms:

• "Allowed memory size exhausted" errors
• Queue stops mid-process
• Large products failing

Solutions:

• Increase memory_limit in PHP settings (256M recommended)
• Enable request delays to reduce concurrent memory usage
• Process smaller batches

4. Rate Limiting Active

If rate-limiting is enabled and triggered, the queue pauses intentionally.

How to check:

1. Go to SWS Pro > Settings > Performance
2. Check if rate-limiting is enabled
3. Look for rate-limit status indicator

Solutions:

• Wait for backlog to clear (automatic)
• Increase rate limit threshold
• Widen the time window

5. Stuck Queue Items

Individual items may be stuck due to errors.

Solutions:

• Check sync logs for specific errors
• Clear stuck items from queue
• Retry failed items manually

Step-by-Step Recovery

Step 1: Check Queue Status

1. Go to SWS Pro > Queue
2. Note the total items pending
3. Check for any items marked as failed

Step 2: Review Recent Logs

1. Go to SWS Pro > Logs
2. Look for error messages
3. Identify patterns (same product failing, timeout errors, etc.)

Step 3: Verify Cron Is Running

Test if WP-Cron is firing:

1. Install WP Crontrol plugin (optional)
2. Check scheduled tasks are executing
3. Or set up server-side cron

→ Server-Side Cron Setup

Step 4: Enable Performance Settings

If you have a large backlog:

1. Go to SWS Pro > Settings > Performance
2. Enable Rate-Limiting
3. Enable Request Delays
4. Save and monitor queue progress

→ Performance Settings Guide

Step 5: Clear Stuck Items (If Needed)

If specific items are blocking the queue:

1. Identify the stuck item in logs
2. Check the source product in Square
3. Fix any data issues
4. Clear and retry the item

Prevention

To prevent future queue stalls:

1. Set up server-side cron — Most reliable solution
2. Enable performance settings — For high-volume catalogs
3. Monitor queue regularly — Catch issues early
4. Review server limits — Ensure adequate PHP resources

Server Requirements

Still Stuck?

If the queue remains stalled:

• Check Products Not Importing guide
• Check Real-Time Sync Issues guide
• Review PHP error logs on your server
• Contact support with your sync logs and queue status