org.apache.flink.runtime.jobmaster.LogicalSlot Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.runtime.jobmaster;
import org.apache.flink.runtime.clusterframework.types.AllocationID;
import org.apache.flink.runtime.jobmanager.scheduler.Locality;
import org.apache.flink.runtime.jobmanager.slots.TaskManagerGateway;
import org.apache.flink.runtime.taskmanager.TaskManagerLocation;
import javax.annotation.Nullable;
import java.util.concurrent.CompletableFuture;
/**
* A logical slot represents a resource on a TaskManager into which a single task can be deployed.
*/
public interface LogicalSlot {
Payload TERMINATED_PAYLOAD =
new Payload() {
private final CompletableFuture completedTerminationFuture =
CompletableFuture.completedFuture(null);
@Override
public void fail(Throwable cause) {
// ignore
}
@Override
public CompletableFuture getTerminalStateFuture() {
return completedTerminationFuture;
}
};
/**
* Return the TaskManager location of this slot.
*
* @return TaskManager location of this slot
*/
TaskManagerLocation getTaskManagerLocation();
/**
* Return the TaskManager gateway to talk to the TaskManager.
*
* @return TaskManager gateway to talk to the TaskManager
*/
TaskManagerGateway getTaskManagerGateway();
/**
* Gets the locality of this slot.
*
* @return locality of this slot
*/
Locality getLocality();
/**
* True if the slot is alive and has not been released.
*
* @return True if the slot is alive, otherwise false if the slot is released
*/
boolean isAlive();
/**
* Tries to assign a payload to this slot. One can only assign a single payload once.
*
* @param payload to be assigned to this slot.
* @return true if the payload could be assigned, otherwise false
*/
boolean tryAssignPayload(Payload payload);
/**
* Returns the set payload or null if none.
*
* @return Payload of this slot of null if none
*/
@Nullable
Payload getPayload();
/**
* Releases this slot.
*
* @return Future which is completed once the slot has been released, in case of a failure it is
* completed exceptionally
* @deprecated Added because extended the actual releaseSlot method with cause parameter.
*/
default CompletableFuture releaseSlot() {
return releaseSlot(null);
}
/**
* Releases this slot.
*
* @param cause why the slot was released or null if none
* @return future which is completed once the slot has been released
*/
CompletableFuture releaseSlot(@Nullable Throwable cause);
/**
* Gets the allocation id of this slot. Multiple logical slots can share the same allocation id.
*
* @return allocation id of this slot
*/
AllocationID getAllocationId();
/**
* Gets the slot request id uniquely identifying the request with which this slot has been
* allocated.
*
* @return Unique id identifying the slot request with which this slot was allocated
*/
SlotRequestId getSlotRequestId();
/** Payload for a logical slot. */
interface Payload {
/**
* Fail the payload with the given cause.
*
* @param cause of the failure
*/
void fail(Throwable cause);
/**
* Gets the terminal state future which is completed once the payload has reached a terminal
* state.
*
* @return Terminal state future
*/
CompletableFuture getTerminalStateFuture();
}
}