Can I plot on ZFS block devices?
(ie, 400 TB devices)
can I plot via SAMBA/CIFS on remote shares???
both works but if you mine on zfs you may require to disable prefetching and tweak some other stuff to optimize the read process.
i can confirm that 250 tb work great

Are you solo mining?
If it takes so long for the plotting, would it make more sense to distribute the plotting over a bunch of computers that are each accessing a large ZFS device (say 1 PB) and plotting seperately? Would it make more sense to carve it up as seperate zVols and present each over 40 gig QDR to the plotter servers, or just hit the main server over 20 GB (2 x 10GB LACP bond) SMB?
It is made up of several hundred SAS disks and has PCI-E SSD level2 caches as well as half a petabyte of RAM for level1 caching.