Deleted data not reflected in Volume/Physical Capacity

Hello guys/gals,

I have a brand new cluster where i created 4 x 256G volumes. I presented these volumes to a vSphere cluster where i created 4 datastores. I then created a 40G VM on each datastore and ran some tests using IOmeter just to generate some workload.

Now i am done with my testing, i deleted my VMs from datastore (Volume Capacity in the GUI did not change, that's understandable).  I then went ahead and deleted the actual datastores from vSphere cluster. Still Volume capacity nor Physical Capacity did not change, they are still displaying the same values as if my datastores were still in place and VMs were up and running.  So next step i went ahead and unmapped volumes from vSphere cluster hoping that would trigger something but nada.

So the question is, does XtremIO run some kind of garbage collection job to actually reflect that data has been deleted from volumes ?  Because there is nothing else on this XtremIO cluster but these 4 volumes.

Thank you