You can check the ashift of the zpool via "zpool get all | grep ashift". If
this is different, it will make a huge difference in space usage. There are a
number of ZFS articles that discuss this, it isn't specific to Lustre.
Also, RAID-Z2 is going to have much more space overhead for the MDT
There isn't really enough information to make any kind of real analysis.
My guess would be that you are using a larger ZFS recordsize or ashift on the
new filesystem, or the RAID config is different?
Cheers, Andreas
On Nov 7, 2019, at 08:45, Hebenstreit, Michael
