Defined in github.com/aws/aws-sdk-go/service/swf/api.go
Optional. The default maximum time, in seconds, before which a worker processing a task must report progress by calling RecordActivityTaskHeartbeat.
You can specify this value only when registering an activity type. The registered default value can be overridden when you schedule a task through the ScheduleActivityTask decision. If the activity worker subsequently attempts to record a heartbeat or returns a result, the activity worker receives an UnknownResource fault. In this case, Amazon SWF no longer considers the activity task to be valid; the activity worker should clean up the activity task.
The duration is specified in seconds; an integer greater than or equal to 0. The value "NONE" can be used to specify unlimited duration.