A load balancing technology segregates various inventory types (e.g.,
potatoes vs. milk, vs. pretzels, vs. tissue paper, etc.) based upon how
frequently they are ordered in a distribution center. Inventory types
that are ordered at the slowest rate are not "replicated" over multiple
pods in the distribution center. Rather, they are constrained to reside
at a single pod within the distribution center. Items that are ordered
somewhat more frequently than those in the slowest group are replicated
in multiple pods across the distribution center. In other words, these
items are separately stocked at locations on more than one pod in the
distribution center. This means that a container passing through the
distribution center can obtain each of the items in the second group of
item types at multiple pods in the distribution center. Thus, these items
do not create a bottleneck in the order fulfillment process. Inventory
types in a third group, the fastest movers, are segregated from items in
the first two groups. They are stored in a separate type of pod that
fulfills orders even faster than the other type of pods.