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Continuous "Queue limit exceeded" errors in API GW logs

Troubleshooting


Problem

There are continuous "Queue limit exceeding" errors in the server log.

2025-09-09 13:32:52 WIB [YAI.0205.0013W] (tid=1044) [default] Error in event publisher submitting com.softwareag.pg.pgmen.processors.LogInvocationProcessor policy engine task to queue. Queue limit exceeded. 
2025-09-09 13:32:52 WIB [YAI.0205.0013W] (tid=1044) [default] Error in event publisher submitting com.softwareag.pg.pgmen.processors.LogInvocationProcessor policy engine task to queue. Queue limit exceeded. 
2025-09-09 13:32:52 WIB [YAI.0205.0013W] (tid=1044) [default] Error in event publisher submitting com.softwareag.pg.pgmen.processors.LogInvocationProcessor policy engine task to queue. Queue limit exceeded. 
 

Symptom

The API GW is experiencing an issue where a large number of transaction logs are being entered into Elasticsearch, and the server log contains repeated error messages indicating that the event publisher is unable to submit tasks to the queue due to a 'Queue limit exceeded' error.

Cause

The issue was caused due to the default thread configuration for handling transactions was insufficient for the high volume of events generated, leading to 'Queue limit exceeded' errors. 

Diagnosing The Problem

  1. Verify server logs to identify the 'Queue limit exceeded' error related to com.softwareag.pg.pgmen.processors.LogInvocationProcessor.
  2. Adjust the following extended settings to improve performance: Double the existing value of max threads for collection and reporting pool.

    events.collectionPool.maxThreads

    events.collectionPool.minThreads

    events.collectionQueue.size

    events.reportingPool.maxThreads

    events.reportingPool.minThreads

    events.reportingQueue.size

     

Resolving The Problem

The issue was caused by the internal queue being full due to slow reporting to Elasticsearch. To resolve:
1. Increase the following extended settings values: Double the count of max threads for collection and reporting pool.
- events.collectionPool.maxThreads
- events.collectionPool.minThreads
- events.collectionQueue.size
- events.reportingPool.maxThreads
- events.reportingPool.minThreads
- events.reportingQueue.size
2. Refer to 'Configuring Extended Settings' in the IBM Documentation for detailed instructions on updating these values.

Configuring Extended Settings - IBM Documentation
3. After increasing the max threads, verify the server log. There shouldn't be any more entries of "Queue limit exceeded" in the server log.

Document Location

Worldwide

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Document Information

Modified date:
06 December 2025

UID

ibm17253856