The AIS Satisficing Reasoning Cycle

The unbounded computation times of the knowledge sources used in the global database directly conflict the AIS designers' desire for limited latencies. For instance, a reasoning cycle which identified the optimal action and performed it next would most likely be very time consuming. In limited domains, such "best-next" strategies may indeed be appropriate, but to provide multi-faceted expertise requires more general approaches.

To this end, the AIS architecture guarantees latencies through interruptibility. The agenda manager works on producing a list of actions, but it can be interrupted at any time by the next stage, the scheduler. This stage of reasoning can likewise be interrupted by the executor. These separate processes satisfy the need for functional asynchrony.

The interrupt conditions for each stage are controlled by dynamic cycle parameters. Adjustments permit focused reasoning by controlling the types of reasoning carried out and the results of each stage. For instance, some parameters for the agenda manager control the time spent developing new actions, while others determine which types of actions are favored over others.

However, the satisficing cycle does make sacrifices for its improved response times. The resulting actions are not necessarily rational with respect to the system's current control plan. The AIS developers are clearly willing to give up optimality in return for time-stress responsivity, graceful degradation, and speed-knowledge independence.

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