Maybe filesystem cache is coming into play here? Your NFS mount is shared storage that could be changing and thus must be queried each time vs a disk/LUN where the filesystem is owned by the client and the state can be cached. Maybe you could unmount both, or better yet, reboot, and mount, and then prior to doing anything run the commands again? And then now without rebooting another time? Just curious to see if there are differences on fresh boot without caches, and then on a repeat where caches could influence.
Cheers,
Chris Madden
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