How To Fix UGMD391 - Overflow of shared memory

SAP Error Message - Details

• Message type: E = Error

• Message class: UGMD - FIN Master Data: Messages

• Message number: 391

• Message text: Overflow of shared memory

What causes this issue?

Overflow of shared memory.

System Response

The system has temporarily deactivated use of the shared memory on
application server &V1&. This has a negative effect on performance.

How to fix this error?

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

Procedure for System Administrators

Increase the memory space reserved for the shared memory. Call up
transaction <DS:TRAN.RZ11>Profile Parameter Maintenance</> and change
the following parameters:
<ZK>rsdb/esm/buffersize_kb</>
<ZK>rsdb/esm/max_objects</>

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message UGMD391 - Overflow of shared memory ?

  The SAP error message UGMD391, which indicates an "Overflow of shared memory," typically occurs when the shared memory allocated for a particular SAP instance is exceeded. This can happen due to various reasons, such as high load on the system, inefficient memory usage by applications, or misconfiguration of memory parameters.
  Causes:
  
  High Load: A sudden increase in user activity or background jobs can lead to excessive memory consumption.
  Configuration Issues: Incorrect settings in the SAP memory parameters (like abap/heap_area_total, abap/heap_area_dia, etc.) can lead to insufficient memory allocation.
  Memory Leaks: Certain applications or custom code may have memory leaks, causing memory to be consumed without being released.
  Insufficient Shared Memory Allocation: The shared memory settings in the operating system may not be sufficient for the needs of the SAP instance.
  
  Solutions:
  
  
  Increase Shared Memory Allocation:
  
  Adjust the shared memory settings in the operating system. For example, on Linux, you can modify the /etc/sysctl.conf file to increase the kernel.shmmax and kernel.shmall parameters.
  Restart the SAP instance after making changes to the operating system settings.
  
  
  
  Review and Adjust SAP Memory Parameters:
  
  Use transaction RZ10 to adjust the profile parameters related to memory. Increase parameters like abap/heap_area_total, abap/heap_area_dia, and others as necessary.
  Monitor the memory usage using transaction ST02 (Tune Summary) to identify if specific areas are under pressure.
  
  
  
  Analyze and Optimize Code:
  
  Review custom ABAP code and background jobs for potential memory leaks or inefficient memory usage.
  Use transaction SE30 (Runtime Analysis) or SAT (ABAP Trace) to analyze performance and memory consumption.
  
  
  
  Monitor System Performance:
  
  Regularly monitor system performance and memory usage to identify trends and potential issues before they lead to overflow.
  Use transaction SM50 to check the status of work processes and memory consumption.
  
  
  
  Consult SAP Notes:
  
  Check the SAP Support Portal for any relevant SAP Notes that may address specific issues related to memory management and the UGMD391 error.
  
  
  
  Related Information:
  
  SAP Memory Management: Understanding how SAP manages memory can help in configuring the system appropriately. SAP uses different memory areas, including heap memory, buffer memory, and shared memory.
  Operating System Limits: Be aware of the operating system's limits on shared memory and ensure they are configured to support the needs of your SAP instance.
  Performance Tuning: Regular performance tuning and monitoring can help prevent memory-related issues from occurring.
  
  If the problem persists after trying the above solutions, it may be beneficial to engage SAP support for further assistance.