vSAN File services is not reclaiming space on a file share after deleting files.

Products

• VMware vSAN

Issue/Introduction

Shared folder(s) on the vSAN File Server appliance continuously grow in size.

Deleting files from the share does not reduce the reported used space.

Performance degradation may be observed due to low storage space.

 

Environment

VMware vSAN (All Versions)

vSAN Files Service

Cause

Deleting files in a file share might not be reflected in vSAN capacity view. (As seen in any vSAN version release notes)

• The allocated blocks may not be returned back to the vSAN storage instantly after all the files are deleted and hence it would take some time before the reclaimed storage capacity to be updated in vSAN capacity view. Also, when new data is written to the same file share, these deleted blocks might get reused prior to returning them to vSAN storage.
  
  
• If unmap is enabled and vSAN deduplication is disabled, the space may not be freed back to vSAN unless 4MB aligned space are freed in VDFS. If unmap is enabled and vSAN deduplication is enabled, space freed by VDFS will be freed back to vSAN with a delay.

Resolution

In cases where space reclamation is an urgent priority.

1. Make sure all the data is backed up on the file share. 
2. Then delete the share, recreate it and restore contents from backup.