How To Fix SHMA012 - Instances of the class &1 cannot be created in the shared memory.

SAP Error Message - Details

• Message type: E = Error

• Message class: SHMA - Shared Objects: Management Messages

• Message number: 012

• Message text: Instances of the class &1 cannot be created in the shared memory.

What causes this issue?

A root data class must be specified for each area. The attributes of
this class are the actual visible data of the area. This class must be
markd as "shared memory enabled" in its properties in the Class Builder.
This signals that the class is prepared for having its instances also
in the shared objects memory. However, you have specified a class that
is not marked in this way.

System Response

Error Message

How to fix this error?

Enter a root data class that is marked as "shared memory enabled" or set
this attribute in the Class Builder (SE24) for the selected class.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message SHMA012 - Instances of the class &1 cannot be created in the shared memory. ?

  The SAP error message SHMA012 indicates that instances of a specific class cannot be created in shared memory. This typically occurs when there are issues related to the configuration or management of shared memory in the SAP system.
  Cause:
  
  Insufficient Memory: The shared memory area may be full or not properly allocated, preventing new instances from being created.
  Configuration Issues: The parameters for shared memory management may not be set correctly in the SAP system.
  System Limits: The system may have reached its limit for the number of instances that can be created for that particular class.
  Authorization Issues: The user or process attempting to create the instance may not have the necessary authorizations.
  Kernel Issues: There may be bugs or issues in the SAP kernel that affect shared memory management.
  
  Solution:
  
  
  Check Memory Allocation:
  
  Use transaction code RZ10 to check and adjust the profile parameters related to shared memory. Look for parameters like shm_max_size and shm_min_size.
  Ensure that the shared memory is adequately sized for your application needs.
  
  
  
  Monitor Shared Memory Usage:
  
  Use transaction SMEM to monitor the usage of shared memory and identify if it is full or if there are any leaks.
  
  
  
  Adjust Configuration:
  
  Review the configuration settings in the instance profile and adjust them as necessary. You may need to increase the size of the shared memory segments.
  
  
  
  Restart the Instance:
  
  Sometimes, simply restarting the SAP instance can resolve temporary issues with shared memory.
  
  
  
  Check Authorizations:
  
  Ensure that the user or process has the necessary authorizations to create instances in shared memory.
  
  
  
  Kernel Upgrade:
  
  If the issue persists, consider upgrading the SAP kernel to the latest version, as it may contain fixes for known issues related to shared memory.
  
  
  
  Consult SAP Notes:
  
  Check the SAP Support Portal for any relevant SAP Notes that may address this specific error message or provide additional troubleshooting steps.
  
  
  
  Related Information:
  
  
  Transaction Codes: 
  
  RZ10 (Profile Maintenance)
  SMEM (Shared Memory Management)
  SM21 (System Log)
  ST22 (Dump Analysis)
  
  
  
  SAP Documentation: Refer to the official SAP documentation for detailed information on shared memory management and configuration.
  
  
  SAP Community: Engage with the SAP Community forums for insights from other users who may have encountered similar issues.
  
  
  If the problem persists after trying the above solutions, it may be necessary to contact SAP support for further assistance.