NFSv4

I didn't find much of a difference in speed by using NFSv4.2. I also tried playing with rsize & wsize but there was no difference so I've left those as the default of 1MB.

Configure

To mount /home as NFSv4.2 you don't need to change much just the following;

ltsp nfs --nfs-home=1

Change /etc/ltsp/ltsp.conf to

FSTAB_HOME="server:/home /home nfs4 nfsvers=4.2,defaults,nolock 0 0"

Make sure the client chroot contains /sbin/mount.nfs4 (package nfs-common in Debian/Ubuntu).

Checking

Once you have booted your fat-client then check the /home is mounted as nfs4 by typing the 'mount' command and look for the /home and check it says nfs4.