How To Fix ICM504 - Max. number of threads reached

SAP Error Message - Details

• Message type: E = Error

• Message class: ICM - Messages for ICM Monitor

• Message number: 504

• Message text: Max. number of threads reached

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

Unfortunately, there isn't any extra information in this error notice.

What else can you do?

First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).

Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.

You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.

Smart SAP Assistant

• What is the cause and solution for SAP error message ICM504 - Max. number of threads reached ?

  The SAP error message ICM504: Max. number of threads reached typically occurs in the Internet Communication Manager (ICM) when the maximum number of threads that can be created for handling requests has been reached. This can lead to performance issues or the inability to process new incoming requests.
  Causes:
  
  High Load: The system is experiencing a high volume of requests, which exceeds the configured maximum number of threads.
  Configuration Limits: The ICM is configured with a low maximum number of threads, which may not be sufficient for the current workload.
  Resource Constraints: The underlying operating system or hardware may have limitations on the number of threads that can be created.
  Long-Running Requests: If requests take a long time to process, they can occupy threads for extended periods, leading to exhaustion of available threads.
  Memory Issues: Insufficient memory can prevent the creation of new threads.
  
  Solutions:
  
  
  Increase Maximum Threads:
  
  You can increase the maximum number of threads in the ICM configuration. This can be done by adjusting the parameter icm/MaxConn in the SAP profile.
  Example: Set icm/MaxConn to a higher value based on your system's capacity and expected load.
  
  
  
  Optimize Application Performance:
  
  Review and optimize the applications running on the SAP system to ensure they are not taking too long to process requests.
  Identify and resolve any bottlenecks in the application logic or database queries.
  
  
  
  Monitor and Analyze Load:
  
  Use monitoring tools to analyze the load on the ICM and identify peak usage times.
  Consider load balancing or scaling out the application if necessary.
  
  
  
  Check System Resources:
  
  Ensure that the server has adequate CPU and memory resources to handle the expected load.
  Monitor system performance and consider upgrading hardware if necessary.
  
  
  
  Review Long-Running Transactions:
  
  Identify any long-running transactions that may be holding up threads and optimize them.
  
  
  
  Restart ICM:
  
  In some cases, restarting the ICM can help clear up any stuck threads and free up resources.
  
  
  
  Related Information:
  
  SAP Notes: Check SAP Notes related to ICM and thread management for specific guidance and best practices.
  SAP Documentation: Refer to the official SAP documentation for detailed information on configuring ICM parameters.
  Monitoring Tools: Use tools like SAP Solution Manager or other monitoring solutions to keep track of system performance and thread usage.
  
  By addressing the underlying causes and implementing the suggested solutions, you can mitigate the occurrence of the ICM504 error and improve the overall performance of your SAP system.