How To Fix WRF_REF401 - No system resources available for parallel processing! -> Serialisation!

WRF_REF401 - Overview

• Message type: E = Error

• Message class: WRF_REF - Messages from References for Materials Without History

• Message number: 401

• Message text: No system resources available for parallel processing! -> Serialisation!

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.

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Smart SAP Assistant

• What is the cause and solution for SAP error message WRF_REF401 - No system resources available for parallel processing! -> Serialisation! ?

  The SAP error message WRF_REF401 indicates that there are no system resources available for parallel processing, leading to serialization. This typically occurs in the context of SAP's Advanced Planning and Optimization (APO) or other modules that require parallel processing capabilities.
  
  Cause:
  
  Resource Limitations: The system may be running out of available resources (CPU, memory, etc.) to handle parallel processing requests. This can happen if there are too many concurrent processes or if the system is under heavy load.
  
  Configuration Issues: The system may not be configured optimally for parallel processing. This includes settings related to the number of parallel processes allowed or the configuration of background jobs.
  Locks and Contention: There may be locks on certain resources that prevent parallel processing from occurring, leading to serialization.
  System Performance: If the system is experiencing performance issues, it may not be able to allocate resources for parallel processing effectively.
  
  
  Solution:
  
  Monitor System Resources: Use transaction codes like SM50 or