Greetings, Seems like someone is hearing more rumors than I about DOT 8.0. I assume this feature you are speaking of will be very similar to the "striped volume" feature on GX, and not a true 100T volume
Don't keep your hopes too high. The bottleneck ends up being the MDV -- essentially another volume that keeps the metadata for the striped volumes. I also don't believe we have the ability in GX to snapmirror (or volume mirror) a striped volume.
Did you hear this information from a sales person?
No, I'm just responding to to the earlier toasters thread.
I'm not talking about striped volumes -- just regular aggregates, volumes, and files, all of which are limited to 16T.
The 16T limit comes from using a 32 bit integer to store block id numbers. In WAFL a block is 4K so 4K * (2 ^ 32) = 16T.
I think an engineer once told me that they now store block id numbers in 64 bit integers, but have not raised the limit because they need to redesign any algorithms that do not scale gracefully. Since DOT 8.x is a major upgrade from 7.x (where aggregates, flex vols, flex clones, etc., were first introduced) I am hoping that the 16T limit will be increased significantly.
Overall I am very pleased with netapp, but this 16T limit has got to be costing them business, since several of their competitors (Isilon, BlueArc) allow single volumes of over a petabyte.
Steve Losen scl@virginia.edu phone: 434-924-0640
University of Virginia ITC Unix Support