sanha commented on a change in pull request #1: [NEMO-26] Implement SourceLocationAwareSchedulingPolicy URL: https://github.com/apache/incubator-nemo/pull/1#discussion_r173046431
########## File path: runtime/master/src/main/java/edu/snu/nemo/runtime/master/scheduler/SourceLocationAwareSchedulingPolicy.java ########## @@ -0,0 +1,236 @@ +/* + * Copyright (C) 2018 Seoul National University + * + * Licensed 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 edu.snu.nemo.runtime.master.scheduler; + +import edu.snu.nemo.common.exception.SchedulingException; +import edu.snu.nemo.common.ir.Readable; +import edu.snu.nemo.common.ir.vertex.executionproperty.ExecutorPlacementProperty; +import edu.snu.nemo.runtime.common.plan.physical.ScheduledTaskGroup; +import edu.snu.nemo.runtime.common.state.TaskGroupState; +import edu.snu.nemo.runtime.master.JobStateManager; +import edu.snu.nemo.runtime.master.resource.ExecutorRepresenter; +import org.apache.reef.annotations.audience.DriverSide; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import javax.annotation.concurrent.ThreadSafe; +import javax.inject.Inject; +import java.util.*; +import java.util.concurrent.ThreadLocalRandom; +import java.util.concurrent.TimeUnit; +import java.util.concurrent.locks.Condition; +import java.util.concurrent.locks.Lock; +import java.util.concurrent.locks.ReentrantLock; +import java.util.stream.Collectors; +import java.util.stream.Stream; + +/** + * This policy is same as {@link RoundRobinSchedulingPolicy}, however for TaskGroups + * with {@link edu.snu.nemo.common.ir.vertex.SourceVertex}, it tries to pick one of the executors + * where the corresponding data resides. + */ +@ThreadSafe +@DriverSide +public final class SourceLocationAwareSchedulingPolicy implements SchedulingPolicy { + private static final Logger LOG = LoggerFactory.getLogger(SourceLocationAwareSchedulingPolicy.class); + + private final ExecutorRegistry executorRegistry; + private final RoundRobinSchedulingPolicy roundRobinSchedulingPolicy; + private final long scheduleTimeoutMs; + private final Lock lock = new ReentrantLock(); + private final Condition moreExecutorsAvailableCondition = lock.newCondition(); + + /** + * Injectable constructor for {@link SourceLocationAwareSchedulingPolicy}. + * @param executorRegistry provides catalog of available executors + * @param roundRobinSchedulingPolicy provides fallback for TaskGroups with no input source information + */ + @Inject + private SourceLocationAwareSchedulingPolicy(final ExecutorRegistry executorRegistry, + final RoundRobinSchedulingPolicy roundRobinSchedulingPolicy) { + this.executorRegistry = executorRegistry; + this.roundRobinSchedulingPolicy = roundRobinSchedulingPolicy; + this.scheduleTimeoutMs = roundRobinSchedulingPolicy.getScheduleTimeoutMs(); + } + + @Override + public long getScheduleTimeoutMs() { + return scheduleTimeoutMs; + } + + /** + * Try to schedule a TaskGroup. + * If the TaskGroup has one or more source tasks, this method schedules the task group to one of the physical nodes, + * chosen from union of set of locations where splits of each source task resides. + * If the TaskGroup has no source tasks, falls back to {@link RoundRobinSchedulingPolicy}. + * @param scheduledTaskGroup to schedule. + * @param jobStateManager jobStateManager which the TaskGroup belongs to. + * @return true if the task group is successfully scheduled, false otherwise. + */ + @Override + public boolean scheduleTaskGroup(final ScheduledTaskGroup scheduledTaskGroup, + final JobStateManager jobStateManager) { + lock.lock(); + try { + Set<String> sourceLocations = Collections.emptySet(); + try { + sourceLocations = getSourceLocations(scheduledTaskGroup.getLogicalTaskIdToReadable().values()); + } catch (final UnsupportedOperationException e) { + // do nothing + } catch (final Exception e) { + LOG.warn(String.format("Exception while trying to get source location for %s", + scheduledTaskGroup.getTaskGroupId()), e); + } + if (sourceLocations.size() == 0) { + // No source location information found, fall back to the RoundRobinSchedulingPolicy + return roundRobinSchedulingPolicy.scheduleTaskGroup(scheduledTaskGroup, jobStateManager); + } + + if (scheduleToLocalNode(scheduledTaskGroup, jobStateManager, sourceLocations)) { + return true; + } else { + try { + moreExecutorsAvailableCondition.await(scheduleTimeoutMs, TimeUnit.MILLISECONDS); Review comment: Let's reduce the default timeout. (Around 50 ms maybe proper.) ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
