"compact_cpg" command is seen executed in HPE storge array system

Products

• VMware vSphere ESXi

Issue/Introduction

The "compact_cpg" command in the context of HPE (Hewlett Packard Enterprise) Storage Array systems is related to the management of "Capacity Pool Groups" (CPG).  
The compact_cpg command is used to consolidates logical disk space/ reclaim or optimize the space in a Capacity Pool Group (CPG). The CPG is essentially a logical construct that HPE Storage arrays use to manage physical storage resources. When you delete data or volumes from a CPG, the storage system may not automatically reclaim that space. Over time, this can lead to inefficient use of storage, known as fragmentation. The compact_cpg command is a manual process that compacts the storage in a CPG, freeing up space and optimizing the storage configuration. This action does not typically result in any data loss, as it is simply an optimization step for better space utilization.

Cause

The presence of the compact_cpg command in the logs is generally not an issue. It is simply an informational message indicating that the system is performing or has completed a compaction process. It is not a critical error or warning, but rather a housekeeping task carried out to ensure efficient use of storage.

If you see this message frequently, it could be an indication that your CPGs are frequently experiencing fragmentation, which might point to heavy data changes, deletions, or migration tasks.

Resolution

This message is generally ignorable, as it is not indicative of a critical system failure. It is simply informing you that compaction has been performed. No immediate action is required to troubleshoot this message. However, you should monitor the system’s storage utilization to see if the compaction process is needed often. Frequent compaction could indicate that the CPGs are not being used efficiently, and you might want to review your storage provisioning strategies or consider expanding the capacity of the CPGs if needed.

If you are concerned about the frequent need to compact the CPG, you may need to evaluate the workload or consult with HPE to optimize the configuration.

Additional Information

This issue is not specifically related to VMware and not a VMware issue. The compact_cpg command pertains to the HPE Storage Array system itself. VMware could indirectly trigger compaction if its workloads are causing heavy deletion or storage reallocation, but the issue lies in the configuration or utilization of the HPE Storage system rather than VMware itself.

Refer: https://support.hpe.com/hpesc/public/docDisplay?docId=a00006229en_us