1 files changed, 81 insertions, 0 deletions
diff --git a/core/src/main/scala/org/apache/spark/scheduler/cluster/SchedulingAlgorithm.scala b/core/src/main/scala/org/apache/spark/scheduler/cluster/SchedulingAlgorithm.scala
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+++ b/core/src/main/scala/org/apache/spark/scheduler/cluster/SchedulingAlgorithm.scala
@@ -0,0 +1,81 @@
+/*
+ * 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.spark.scheduler.cluster
+
+/**
+ * An interface for sort algorithm
+ * FIFO: FIFO algorithm between TaskSetManagers
+ * FS: FS algorithm between Pools, and FIFO or FS within Pools
+ */
+private[spark] trait SchedulingAlgorithm {
+  def comparator(s1: Schedulable, s2: Schedulable): Boolean
+}
+
+private[spark] class FIFOSchedulingAlgorithm extends SchedulingAlgorithm {
+  override def comparator(s1: Schedulable, s2: Schedulable): Boolean = {
+    val priority1 = s1.priority
+    val priority2 = s2.priority
+    var res = math.signum(priority1 - priority2)
+    if (res == 0) {
+      val stageId1 = s1.stageId
+      val stageId2 = s2.stageId
+      res = math.signum(stageId1 - stageId2)
+    }
+    if (res < 0) {
+      return true
+    } else {
+      return false
+    }
+  }
+}
+
+private[spark] class FairSchedulingAlgorithm extends SchedulingAlgorithm {
+  override def comparator(s1: Schedulable, s2: Schedulable): Boolean = {
+    val minShare1 = s1.minShare
+    val minShare2 = s2.minShare
+    val runningTasks1 = s1.runningTasks
+    val runningTasks2 = s2.runningTasks
+    val s1Needy = runningTasks1 < minShare1
+    val s2Needy = runningTasks2 < minShare2
+    val minShareRatio1 = runningTasks1.toDouble / math.max(minShare1, 1.0).toDouble
+    val minShareRatio2 = runningTasks2.toDouble / math.max(minShare2, 1.0).toDouble
+    val taskToWeightRatio1 = runningTasks1.toDouble / s1.weight.toDouble
+    val taskToWeightRatio2 = runningTasks2.toDouble / s2.weight.toDouble
+    var res:Boolean = true
+    var compare:Int = 0
+
+    if (s1Needy && !s2Needy) {
+      return true
+    } else if (!s1Needy && s2Needy) {
+      return false
+    } else if (s1Needy && s2Needy) {
+      compare = minShareRatio1.compareTo(minShareRatio2)
+    } else {
+      compare = taskToWeightRatio1.compareTo(taskToWeightRatio2)
+    }
+
+    if (compare < 0) {
+      return true
+    } else if (compare > 0) {
+      return false
+    } else {
+      return s1.name < s2.name
+    }
+  }
+}
+