Chapter 6. IBM TotalStorage SAN Volume Controller attachment 177
6.2.3 DS6000 Extent Pool implications
An Extent Pool is visible to both of the two servers in the DS6000, but directly managed by
only one of them.You must define a minimum of two Extent Pools with one created for each
storage server to fully exploit the resources. There is a minimum of one Rank per Extent Pool.
Although it is possible to configure many Ranks in an Extent Pool, for SAN Volume Controller
performance optimization, we do not recommend more than one.
If you need to maximize the performance of your SAN Volume Controller configuration,
allocate each Rank to its own Extent Pool so that you configure one Rank per pool. This gives
you the ability to direct our allocations ...