1. A system for evaluating a plurality of proposed states for a storage system that provides service to a plurality of workloads, the system comprising: computer hardware configured for: producing a state tree comprising a plurality of nodes arranged in a plurality of hierarchical levels comprising at least first and second levels, the first level comprising a start node representing a current state of the storage system, the second level comprising a plurality of proposed nodes, each proposed node representing a proposed state of the storage system produced by implementing a set of actions associated with the proposed state that changes the current state of the storage system to the proposed state, wherein the state tree is produced based on original planner information; receiving new planner information; adding at least one proposed node in the state tree based on the new planner information; removing at least one proposed node in the state tree based on the new planner information; and producing a set of proposed nodes remaining in the state tree for selecting a proposed state to implement, wherein: the plurality of proposed nodes are divided into first and second groups of proposed nodes, the first group of proposed nodes representing proposed states capable of being implemented within a first time frame and the second group of proposed nodes representing proposed states capable of being implemented within a second time frame, the first time frame being shorter than the second time frame; the new planner information comprises a time constraint that specifies the first or second time frame; and removing at least one proposed node in the state tree comprises: upon determining that the time constraint specifies the first time frame, removing the second group of proposed nodes from the state tree; and upon determining that the time constraint specifies the second time frame, removing the first group of proposed nodes from the state tree.