Please reduce KVM image size

No idea. (This doesn’t happen for me.)

ran a du -h on the copied sparse file and it gives a 101G. Copying a sparse file seems to destroy this property that it has o.O

du and df indicate that the converted files using your commands are indeed small.

So what do you suggest? Should we try a QED which doesn’t need preallocating for performance gains?

Nevermind , it turns out that running another identical conversion is the way to do it and not a straight copy, The command that you committed works. I think we need to note that a normal copy operation has this effect nonetheless

I found this:
https://wiki.archlinux.org/index.php/sparse_file#Copying_the_sparse_file

In summary, try this:

cp --sparse=always source target

Speed up operations on sparese files with tar, gzip, rsync?