- Datastores are showing "Not consumed" on hosts.
- VMs may fail to vMotion.
- VMs may become orphaned when powered off.
- Snapshot-based backups may fail.
- In vCenter/hosts, snapshot creation and consolidation may fail with: message = "Consolidation failed for disk node 'scsi0:1': 12 (Cannot allocate memory)."
Cause
This is a known issue in VMFS6. In certain workflows, the memory is allocated but not freed up resulting in VMFS heap exhaustion.
The memory allocated gets freed during VMFS resource allocation and hence, creating a eagerzeroedthick file on VMFS datastore is an effective workaround. See the workaround section below for more details.
Resolution
This issue is resolved in vSphere ESXi 7.0 Update 1.
To workaround this issue, follow the steps below:
Create an Eager zeroed thick disk on all of the mounted VMFS6 datastores.
vmkfstools -c 10M -d eagerzeroedthick /vmfs/volumes/datastore/eztDisk
Delete the Eager zeroed thick disk created in step 1.
vmkfstools -U /vmfs/volumes/datastore/eztDisk
The workaround has to be implemented for each datastore on each host.