How To Fix CSM_VMC037 - Maximum Frequency of Full GCs for Individual Virtual Machines

SAP Error Message - Details

• Message type: E = Error

• Message class: CSM_VMC - Messages for VM Container Monitoring

• Message number: 037

• Message text: Maximum Frequency of Full GCs for Individual Virtual Machines

What causes this issue?

Each of the active virtual machines in the VM Container has reserved
memory for its Java heap. The size of this memory is bound to specified
limits when the VM is started and cannot be changed at runtime. Once
this memory is used up, the VM activates the garbage collection (GC)
procedure, in which memory allocated but no longer needed is freed up
again.
There are two stages to this procedure - partial and full garbage
collection. The partial GC cleans up dedicated memory areas only and
uses much less resources. It is therefore much faster than the full GC.
This partial GC is performed more frequently and is part of normal
operation. The full GC is started when the permanent memory usage
(objects that have survived several partial GCs) exceeds specified
limits. Full GC empties all the objects from the Java heap that are no
longer needed, and therefore reduces the amount of memory occupied to
the smallest possible amount. This process involves a complex analysis
of the Java object references and takes a long time and uses up alot of
VM resources.

System Response

This monitor displays the frequency of GC runs in the VM that shows the
biggest value during the cycle measured. This frequency of full GC runs
in the VM is a criterion for the state of memory usage in the VM. A
frequency of several full GCs per minute (10 and more) is an indication
that VM memory is running out and that VM performance may be severely
affected.
You can find more information in the online documentation under
<DS:KENO.001560AA0E081DEB91FE7CAB73A45918>Garbage Collection</>.

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

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CSM_VMC037 - Maximum Frequency of Full GCs for Individual Virtual Machines ?

  The SAP error message CSM_VMC037, which indicates "Maximum Frequency of Full GCs for Individual Virtual Machines," is related to the garbage collection (GC) process in the Java Virtual Machine (JVM) used by SAP applications. This error typically arises when the JVM is experiencing excessive full garbage collection cycles, which can lead to performance degradation and application instability.
  Cause:
  
  Memory Pressure: The application may be consuming more memory than what is allocated, leading to frequent full GCs as the JVM tries to reclaim memory.
  Memory Leaks: There may be memory leaks in the application code, causing objects to remain in memory longer than necessary.
  Improper JVM Configuration: The JVM heap size may not be configured optimally for the workload, leading to frequent GCs.
  High Object Creation Rate: The application may be creating objects at a high rate, which can overwhelm the garbage collector.
  Inefficient GC Algorithm: The garbage collection algorithm being used may not be suitable for the application's workload.
  
  Solution:
  
  Increase Heap Size: Adjust the JVM heap size settings to allocate more memory to the application. This can be done by modifying the -Xms (initial heap size) and -Xmx (maximum heap size) parameters.
  Analyze Memory Usage: Use profiling tools (like VisualVM, Eclipse Memory Analyzer, or SAP's own tools) to analyze memory usage and identify potential memory leaks or areas where memory consumption can be optimized.
  Optimize Code: Review the application code for potential memory leaks or inefficient object usage. Ensure that objects are being released when no longer needed.
  Tune Garbage Collection Settings: Depending on the application workload, consider tuning the garbage collection settings. This may involve changing the GC algorithm (e.g., switching to G1GC or ZGC) or adjusting GC-related parameters.
  Monitor and Adjust: Continuously monitor the application's performance and garbage collection metrics. Adjust the configuration as necessary based on observed behavior.
  Upgrade JVM: If you are using an older version of the JVM, consider upgrading to a newer version that may have improved garbage collection algorithms and performance enhancements.
  
  Related Information:
  
  SAP Notes: Check SAP Notes related to JVM performance and garbage collection for specific recommendations and best practices.
  JVM Documentation: Refer to the official documentation for the JVM being used to understand the various garbage collection options and tuning parameters.
  Performance Monitoring Tools: Utilize SAP's monitoring tools (like SAP Solution Manager) to keep track of application performance and JVM health.
  
  By addressing the underlying causes of excessive full garbage collections, you can improve the performance and stability of your SAP application.