Define chunks and create dbslices so that you can distribute table fragments appropriately on disks owned by all coservers, depending on how applications use the tables. Disk space layout affects the following interrelated performance issues:
Frequently used table fragments should be stored on separate disks to prevent I/O contention as well as data contention.
During a table scan, each fragment is scanned separately. Distribute table fragments across disks to equalize the I/O among disks and across coservers as much as possible.