3.8 Timing issue

Time is defined in action semantics to precisely express the behavior of models, which may be sequential or concurrent.

For sequential models or parts of models, the ordering of action executions conforms to the timing causality. A sequence of actions is executed one by one.

For concurrent models or parts of models, the ordering of action executions is unimportant, unless different actions are required to be synchronized to access shared variables. Without explicit synchronization, actions may be executed concurrently or in a meta-model-dependent order.