Package io.trino.execution.scheduler

Interface StageScheduler

All Superinterfaces:

AutoCloseable, Closeable

All Known Implementing Classes:

FixedCountScheduler, FixedSourcePartitionedScheduler, MultiSourcePartitionedScheduler, ScaledWriterScheduler

public interface StageScheduler
extends Closeable

Method Summary

Modifier and Type	Method	Description
default void	close()
ScheduleResult	schedule()	Schedules as much work as possible without blocking.
default void	start()	Called by the query scheduler when the scheduling process begins.

Method Details

start

default void start()

Called by the query scheduler when the scheduling process begins. This method is called before the ExecutionSchedule takes a decision to schedule a stage but after the query scheduling has been fully initialized. Within this method the scheduler may decide to schedule tasks that are necessary for query execution to make progress. For example the scheduler may decide to schedule a task without assigning any splits to unblock dynamic filter collection.

schedule

ScheduleResult schedule()

Schedules as much work as possible without blocking. The schedule results is a hint to the query scheduler if and when the stage scheduler should be invoked again. It is important to note that this is only a hint and the query scheduler may call the schedule method at any time.

close

default void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable