Thin provisioning and fragmentation level of vmdk

[Schaedle]

Hi,

is there a way to get a report how much fragmented my thin provisioned disks are ?

Is there a way to defragment thin disks without vmotion to another datastore ?

Regards Wolfgang

[npadmani · Accepted solution]

Currently there is no tool to measure the degree of fragmentation that exists in vSphere. And the only
utility to defragment a VMDK file is VMotion – to move the VMhome to another datastore and then SVM it back to the original datastore.

Above quote has been taken from Page 10 of following Technical white paper published by vmware

http://www.vmware.com/files/pdf/VMware-DynamicStorageProv-WP-EN.pdf

answers both your questions.

[Schaedle]

Thanks. That's what I thought or I already knew. I hoped there is maybe a third-party tool available.

[continuum]

Well there is no reporting tool that I am aware of  - however you can use vmkfstools -t 0 vmdk to find out the number of fragments.
For large vmdks you can often find 10.000 fragments and more ...
To defrag such a vmdk you can use dd while the VM is powered off.

Ulli