Appendix A Engine Startup and Shutdown Sequence

Appendix A
This section helps you understand the main actions that occur during engine startup and shutdown (in normal circumstances). In any particular project only some of the actions may be required. For example, a project may have no startup rule functions. See Working With Startup and Shutdown Rule Functions for related information.
This section assumes cache OM. It provides the main milestones only and focuses on nodes running inference agents.
Startup Sequence
During engine startup the following actions occur:
1.
If persistence OM is used, the location of the Berkeley DB software it is using, and information about what was recovered from the database.
2.
If a backing store is in use (Cache OM only), cache data is recovered from the backing store and populates cache servers (and JVMs of any other storage enabled agents).
(Cache OM only) Inactive Nodes  If all agents in an engine (node) are inactive, then this ends the startup sequence for that engine.
3.
4.
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6.
The first RTC cycle occurs and all rule actions that are eligible to execute now execute. (Scorecards and startup rule functions can cause rules to be eligible to execute. Depending on the state of entities recovered from the backing store, the RTC will take more or less time.) See Understanding Conflict Resolution and Run to Completion Cycles for more details about RTC cycles.
7.
8.
Rule-based events (recovered or scheduled in a startup action) are asserted after the specified delay. The delay begins when the rule or rule function action executes, so at startup, it is possible for time events to have passed their start time, and they are asserted immediately.
9.
Shutdown Sequence
During engine shutdown the following main actions occur:
1.
2.
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4.