Error
Error Code:
4121
MySQL Error 4121: Query Threads Exceed Limit
Description
This error indicates that the number of query threads currently active within a specific thread group has surpassed the maximum transaction threads allowed for that group. It signifies a resource contention or misconfiguration related to server-side thread management, preventing further queries within that group from executing.
Error Message
Query threads count(%u) exceeds transaction threads limit(%u) per group. Please use query threads count per group smaller or equal to max transaction threads limit per group
Known Causes
3 known causesLow Transaction Thread Limit
The `transaction_thread_limit` setting for a thread group is configured lower than the actual demand for concurrent query threads.
High Concurrent Workload
A surge in concurrent queries or long-running transactions within a specific thread group causes the active query threads to exceed the defined limit.
Inefficient Queries
Poorly optimized SQL queries or transactions that hold query threads for an extended duration can exhaust the available limit in a thread group.
Solutions
Coming SoonDetailed step-by-step solutions for this error are being prepared. In the meantime, try these general troubleshooting tips:
General Troubleshooting Tips
- Check the error message carefully for specific details
- Review recent changes that might have caused the error
- Search for the exact error code in the official documentation
- Check log files for additional context
- Try restarting the application or service