can/do thin provisioned filesystems in stratis dynamically grow AND shrink?

[dnaspliceoflife]

Posted this in the RHA Educators forum but this might be the better home for this question:

---------------------

So I was covering stratis the other day and was waxing poetic about the benefits of thin-provisioning of filesystems on a stratis pool.

We did the guided exercise where we created a nice 2GB file and saw the filesystem grow. We took a snapshot of the filesystem, deleted a file and restored it from the snapshot.

We were also playing around with the various commands that let us view the current state of the system (stratis blockdev list, stratis filesystem list, etc.) and a student asked if the size of the filesystem decreases if you delete a file. I assumed yes since it was thin provisioned. 

We examined the filesystem size with the 2GB file, removed the 2GB file and looked at the filiesystem's size again. It was the same size (~ 2.5 GB) even though there was now only a single < 1K file on the system. I was expecting it to shrink to the min filesystem size of 512MB.

I understand that thin provisioning is great for dynamically growing the filesystem but shouldn't it also be dynamic in the other direction? I'm still relatively new to stratis so there is probably something I'm missing.

Could anyone provide some insight?

Thanks

Mike

[Chetan_Tiwary_]

Hi @dnaspliceoflife ,

Not a stratis expert but my 2 cents here :

You can't shrink its size but if it is allocated from a thin-provisioned pool you can reclaim unused portions.