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nloupet
Contributor
Contributor

Space Efficiency

Hi all

I have an esxi 6.5 with latest updates to my home lab, with 3 local ssd disks 250GB each as datastores vmfs 6 formated.

I have some windows VMs Thin provisioning.

In windows, disks are shown as thin provisioned drives and optimization is available.

If i use thick disks windows recognize them as SSD and i get optimization is not available.

No matter what cluster size is (4K to 64K) when i write and delete files in disks i see that space efficiency is reduced.

Now in a Win10 VM i see needs optimization and 25% space efficiency. All files from disk are deleted and the drive is empty.(see attached pictures)

Running optimize-volume -retrim -slabconsolidate does not help.

Status deos not change. Needs optimization and space efficiency 25% again

If i format the disk space efficiency will returned back to 100%

So what is space efficiency in thin provisioned disks (or in windows) and how to get back to 100% ???

This happened to all my Windows VMs soon or later with variable space efficiency percents (%)

Except that everything is working as expected (umap initiated from VM, reclaiming free space, ....)

*English is not my native language so i am sorry for some syntax errors....

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2 Replies
mhampto
VMware Employee
VMware Employee

Best I can find on what is needed here is the system wants to defrag the drive. The storage of the base disk is still controlled by the ESXi host and could be more fragmented.

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nloupet
Contributor
Contributor

What system?? Windows or ESXI??

Already told that windows drive optimize does not change anything.

Same results with defrag command.

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