[CentOS] LVM thin volumes fstrim operation not supported

[Chris Murphy]

My guess? The passthrough  is causing the error when the command passes
through to the actual device, which doesn't support Trim.

I don't know how it actually works, but you can try to poke it with this
stick: copy a large file to this LV. Check the LV with lvdisplay. Delete
the file. Fstrim. Lvdisplay. Now compare the two lvdisplay results.

It should show the PEs used are less after fstrim.


Chris Murphy