Well, I know what a controller is, and a node...when in context.
You havent described your goals, what you have, what you DONT have...
What we need to agree on, is that RG's are not performance level objects.
What we also need to agree on, is that we need to know what you're trying to do, to answer what you might wanna do with what you have.
Whats your goal?
To configure the aggregates on my six node with something less than every last disk I have (80) so that extras are available that I can add to nodes that need it in the (somewhat unpredictable) future. This way I’m not forced to buy new disks or shelves when I have perhaps severely underutilized disks on one node that I can’t reassign because they’re locked in an aggregate. All the while, I only wish to do this to the extent that performance is not impacted too greatly – say 10 or 15%.
Six node Cmode cluster? Three HA pairs? Six single controller standalone systems?
"This way I’m not forced to buy new disks or shelves when I have perhaps severely underutilized disks on one node"
Well this part is simple.
What's your business plan say you need to do...for what applications, for what workloads, for how long.
==================== (Any Netapp Partners here going to Insight? Stop & say hi in TR-2-140 and TR-2-141..they made me present this year)