com.netflix.fenzo.queues

Interface TaskQueue

All Superinterfaces:

TaskIterator

All Known Subinterfaces:

InternalTaskQueue

All Known Implementing Classes:

TieredQueue

public interface TaskQueue
extends TaskIterator

This interface defines a task queue that contains all tasks that are either pending resource allocation or assigned resources while continuing to run. When using task queues, tasks are input into Fenzo once. The tasks are then maintained in the queue until the task is explicitly removed due to no longer requiring resource assignment, or if the task completed for any reason.

Methods in this interface are expected to be called concurrently. For example, tasks may be added to or removed from the queue while a scheduling iteration using this queue is in progress. Implementations must handle this.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	TaskQueue.TaskState Tasks in a queue are said to be in one of two states.

Method Summary

Modifier and Type	Method and Description
void	queueTask(QueuableTask task) Add a task to the queue.
void	setSla(TaskQueueSla sla) Set SLA for the queue.

Methods inherited from interface com.netflix.fenzo.TaskIterator

next

Method Detail

queueTask

void queueTask(QueuableTask task)

Add a task to the queue. Duplicates are not allowed, as in, a task request that has the same Id as another existing element will be rejected. The added task will be assigned resources by a scheduler. To add a task into Fenzo that is already running from before, use TaskSchedulingService.initializeRunningTask(QueuableTask, String).

This operation is designed to be performed asynchronously, when it is safe to modify the queue. The queue implementations generally do not modify the queue while a scheduling iteration is in progress.

Parameters:

task - A task to add to the queue.

setSla

void setSla(TaskQueueSla sla)
     throws java.lang.IllegalArgumentException

Set SLA for the queue. The queue implementation determines the implementation of TaskQueueSla that is accepted.

Parameters:

sla - The SLA to set for the queue.

Throws:

java.lang.IllegalArgumentException - if the implementation of the TaskQueueSla is incompatible with the queue implementation.