Spark Executor GC Heuristic (#311)

app-conf/HeuristicConf.xml

@@ -193,5 +193,11 @@
     <classname>com.linkedin.drelephant.spark.heuristics.StagesHeuristic</classname>
     <viewname>views.html.help.spark.helpStagesHeuristic</viewname>
   </heuristic>
+  <heuristic>
+    <applicationtype>spark</applicationtype>
+    <heuristicname>Executor GC</heuristicname>
+    <classname>com.linkedin.drelephant.spark.heuristics.ExecutorGcHeuristic</classname>
+    <viewname>views.html.help.spark.helpExecutorGcHeuristic</viewname>
+  </heuristic>
 
 </heuristics>

app/com/linkedin/drelephant/spark/fetchers/statusapiv1/statusapiv1.scala

@@ -87,6 +87,7 @@ trait ExecutorSummary{
   def totalShuffleRead: Long
   def totalShuffleWrite: Long
   def maxMemory: Long
+  def totalGCTime: Long
   def executorLogs: Map[String, String]}
 
 trait JobData{
@@ -292,6 +293,7 @@ class ExecutorSummaryImpl(
   var totalShuffleRead: Long,
   var totalShuffleWrite: Long,
   var maxMemory: Long,
+  var totalGCTime: Long,
   var executorLogs: Map[String, String]) extends ExecutorSummary
 
 class JobDataImpl(

app/com/linkedin/drelephant/spark/heuristics/ExecutorGcHeuristic.scala

@@ -0,0 +1,119 @@
+/*
+ * Copyright 2016 LinkedIn Corp.
+ *
+ * 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 com.linkedin.drelephant.spark.heuristics
+
+import com.linkedin.drelephant.analysis.Severity
+import com.linkedin.drelephant.spark.fetchers.statusapiv1._
+import com.linkedin.drelephant.analysis._
+import com.linkedin.drelephant.configurations.heuristic.HeuristicConfigurationData
+import com.linkedin.drelephant.spark.data.SparkApplicationData
+
+import scala.collection.JavaConverters
+
+/**
+  * A heuristic based on GC time and CPU run time. It calculates the ratio of the total time a job spends in GC to the total run time of a job and warns if too much time is spent in GC.
+  */
+class ExecutorGcHeuristic(private val heuristicConfigurationData: HeuristicConfigurationData)
+  extends Heuristic[SparkApplicationData] {
+
+  import ExecutorGcHeuristic._
+  import JavaConverters._
+
+  val gcSeverityAThresholds: SeverityThresholds =
+    SeverityThresholds.parse(heuristicConfigurationData.getParamMap.get(GC_SEVERITY_A_THRESHOLDS_KEY), ascending = true)
+      .getOrElse(DEFAULT_GC_SEVERITY_A_THRESHOLDS)
+
+  val gcSeverityDThresholds: SeverityThresholds =
+    SeverityThresholds.parse(heuristicConfigurationData.getParamMap.get(GC_SEVERITY_D_THRESHOLDS_KEY), ascending = true)
+      .getOrElse(DEFAULT_GC_SEVERITY_D_THRESHOLDS)
+
+  override def getHeuristicConfData(): HeuristicConfigurationData = heuristicConfigurationData
+
+  override def apply(data: SparkApplicationData): HeuristicResult = {
+    val evaluator = new Evaluator(this, data)
+    var resultDetails = Seq(
+      new HeuristicResultDetails("GC time to Executor Run time ratio", evaluator.ratio.toString),
+      new HeuristicResultDetails("Total GC time", evaluator.jvmTime.toString),
+      new HeuristicResultDetails("Total Executor Runtime", evaluator.executorRunTimeTotal.toString)
+    )
+
+    //adding recommendations to the result, severityTimeA corresponds to the ascending severity calculation
+    if (evaluator.severityTimeA.getValue > Severity.LOW.getValue) {
+      resultDetails = resultDetails :+ new HeuristicResultDetails("Gc ratio high", "The job is spending too much time on GC. We recommend increasing the executor memory.")
+    }
+    //severityTimeD corresponds to the descending severity calculation
+    if (evaluator.severityTimeD.getValue > Severity.LOW.getValue) {
+      resultDetails = resultDetails :+ new HeuristicResultDetails("Gc ratio low", "The job is spending too less time in GC. Please check if you have asked for more executor memory than required.")
+    }
+
+    val result = new HeuristicResult(
+      heuristicConfigurationData.getClassName,
+      heuristicConfigurationData.getHeuristicName,
+      evaluator.severityTimeA,
+      0,
+      resultDetails.asJava
+    )
+    result
+  }
+}
+
+object ExecutorGcHeuristic {
+  val SPARK_EXECUTOR_MEMORY = "spark.executor.memory"
+  val SPARK_EXECUTOR_CORES = "spark.executor.cores"
+
+  /** The ascending severity thresholds for the ratio of JVM GC Time and executor Run Time (checking whether ratio is above normal)
+    * These thresholds are experimental and are likely to change */
+  val DEFAULT_GC_SEVERITY_A_THRESHOLDS =
+    SeverityThresholds(low = 0.08D, moderate = 0.1D, severe = 0.15D, critical = 0.2D, ascending = true)
+
+  /** The descending severity thresholds for the ratio of JVM GC Time and executor Run Time (checking whether ratio is below normal)
+    * These thresholds are experimental and are likely to change */
+  val DEFAULT_GC_SEVERITY_D_THRESHOLDS =
+    SeverityThresholds(low = 0.05D, moderate = 0.04D, severe = 0.03D, critical = 0.01D, ascending = false)
+
+  val GC_SEVERITY_A_THRESHOLDS_KEY: String = "gc_severity_A_threshold"
+  val GC_SEVERITY_D_THRESHOLDS_KEY: String = "gc_severity_D_threshold"
+
+  class Evaluator(executorGcHeuristic: ExecutorGcHeuristic, data: SparkApplicationData) {
+    lazy val executorAndDriverSummaries: Seq[ExecutorSummary] = data.executorSummaries
+    lazy val executorSummaries: Seq[ExecutorSummary] = executorAndDriverSummaries.filterNot(_.id.equals("driver"))
+    lazy val appConfigurationProperties: Map[String, String] =
+      data.appConfigurationProperties
+    var (jvmTime, executorRunTimeTotal) = getTimeValues(executorSummaries)
+
+    var ratio: Double = jvmTime.toDouble / executorRunTimeTotal.toDouble
+
+    lazy val severityTimeA: Severity = executorGcHeuristic.gcSeverityAThresholds.severityOf(ratio)
+    lazy val severityTimeD: Severity = executorGcHeuristic.gcSeverityDThresholds.severityOf(ratio)
+
+    /**
+      * returns the total JVM GC Time and total executor Run Time across all stages
+      * @param executorSummaries
+      * @return
+      */
+    private def getTimeValues(executorSummaries: Seq[ExecutorSummary]): (Long, Long) = {
+      var jvmGcTimeTotal: Long = 0
+      var executorRunTimeTotal: Long = 0
+      executorSummaries.foreach(executorSummary => {
+        jvmGcTimeTotal+=executorSummary.totalGCTime
+        executorRunTimeTotal+=executorSummary.totalDuration
+      })
+      (jvmGcTimeTotal, executorRunTimeTotal)
+    }
+  }
+}
+

app/com/linkedin/drelephant/spark/legacydata/LegacyDataConverters.scala

@@ -173,6 +173,7 @@ object LegacyDataConverters {
         executorInfo.shuffleRead,
         executorInfo.shuffleWrite,
         executorInfo.maxMem,
+        executorInfo.totalGCTime,
         executorLogs = Map.empty
       )
     }

app/com/linkedin/drelephant/spark/legacydata/SparkExecutorData.java

@@ -43,14 +43,15 @@ public static class ExecutorInfo {
     public long inputBytes = 0L;
     public long outputBytes = 0L;
     public long shuffleRead = 0L;
+    public long totalGCTime = 0L;
     public long shuffleWrite = 0L;
 
     public String toString() {
       return "{execId: " + execId + ", hostPort:" + hostPort + " , rddBlocks: " + rddBlocks + ", memUsed: " + memUsed
           + ", maxMem: " + maxMem + ", diskUsed: " + diskUsed + ", totalTasks" + totalTasks + ", tasksActive: "
           + activeTasks + ", tasksComplete: " + completedTasks + ", tasksFailed: " + failedTasks + ", duration: "
           + duration + ", inputBytes: " + inputBytes + ", outputBytes:" + outputBytes + ", shuffleRead: " + shuffleRead
-          + ", shuffleWrite: " + shuffleWrite + "}";
+          + ", shuffleWrite: " + shuffleWrite + ", totalGCTime: " + totalGCTime + "}";
     }
   }
 

app/views/help/spark/helpExecutorGcHeuristic.scala.html

@@ -0,0 +1,20 @@
+@*
+* Copyright 2016 LinkedIn Corp.
+*
+* 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.
+*@
+
+<p>This analysis shows how much time a job is spending in GC. To normalise the results across all jobs, the ratio of the time a job spends in Gc to the total run time of the job is calculated. </p>
+<p>A job is flagged if the ratio is too high, meaning the job spends too much time in GC.</p>
+<h3>Suggestions</h3>
+<p>We recommend increasing the executor memory.</p>

test/com/linkedin/drelephant/spark/SparkMetricsAggregatorTest.scala

@@ -194,6 +194,7 @@ object SparkMetricsAggregatorTest {
     totalShuffleRead = 0,
     totalShuffleWrite = 0,
     maxMemory = 0,
+    totalGCTime = 0,
     executorLogs = Map.empty
   )
 }

test/com/linkedin/drelephant/spark/heuristics/ExecutorGcHeuristicTest.scala

@@ -0,0 +1,138 @@
+/*
+ * Copyright 2016 LinkedIn Corp.
+ *
+ * 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 com.linkedin.drelephant.spark.heuristics
+
+import scala.collection.JavaConverters
+import com.linkedin.drelephant.analysis.{ApplicationType, Severity, SeverityThresholds}
+import com.linkedin.drelephant.configurations.heuristic.HeuristicConfigurationData
+import com.linkedin.drelephant.spark.data.{SparkApplicationData, SparkLogDerivedData, SparkRestDerivedData}
+import com.linkedin.drelephant.spark.fetchers.statusapiv1.{ApplicationInfoImpl, ExecutorSummaryImpl, StageDataImpl}
+import org.apache.spark.scheduler.SparkListenerEnvironmentUpdate
+import org.scalatest.{FunSpec, Matchers}
+
+import scala.concurrent.duration.Duration
+
+
+class ExecutorGcHeuristicTest extends FunSpec with Matchers {
+  import ExecutorGcHeuristicTest._
+
+  describe("ExecutorGcHeuristic") {
+    val heuristicConfigurationData = newFakeHeuristicConfigurationData(
+      Map(
+        "max_to_median_ratio_severity_thresholds" -> "1.414,2,4,16",
+        "ignore_max_bytes_less_than_threshold" -> "4000000",
+        "ignore_max_millis_less_than_threshold" -> "4000001"
+      )
+    )
+    val executorGcHeuristic = new ExecutorGcHeuristic(heuristicConfigurationData)
+
+    val executorSummaries = Seq(
+      newFakeExecutorSummary(
+        id = "1",
+        totalGCTime = Duration("2min").toMillis,
+        totalDuration = Duration("15min").toMillis
+      ),
+      newFakeExecutorSummary(
+        id = "2",
+        totalGCTime = Duration("6min").toMillis,
+        totalDuration = Duration("14min").toMillis
+      ),
+      newFakeExecutorSummary(
+        id = "3",
+        totalGCTime = Duration("4min").toMillis,
+        totalDuration = Duration("20min").toMillis
+      ),
+      newFakeExecutorSummary(
+        id = "4",
+        totalGCTime = Duration("8min").toMillis,
+        totalDuration = Duration("30min").toMillis
+      )
+    )
+
+    describe(".apply") {
+      val data1 = newFakeSparkApplicationData(executorSummaries)
+      val heuristicResult = executorGcHeuristic.apply(data1)
+      val heuristicResultDetails = heuristicResult.getHeuristicResultDetails
+
+      it("returns the severity") {
+        heuristicResult.getSeverity should be(Severity.CRITICAL)
+      }
+
+      it("returns the JVM GC time to Executor Run time duration") {
+        val details = heuristicResultDetails.get(0)
+        details.getName should include("GC time to Executor Run time ratio")
+        details.getValue should include("0.2531")
+      }
+
+      it("returns the total GC time") {
+        val details = heuristicResultDetails.get(1)
+        details.getName should include("Total GC time")
+        details.getValue should be("1200000")
+      }
+
+      it("returns the executor's run time") {
+        val details = heuristicResultDetails.get(2)
+        details.getName should include("Total Executor Runtime")
+        details.getValue should be("4740000")
+      }
+    }
+  }
+}
+
+object ExecutorGcHeuristicTest {
+  import JavaConverters._
+
+  def newFakeHeuristicConfigurationData(params: Map[String, String] = Map.empty): HeuristicConfigurationData =
+    new HeuristicConfigurationData("heuristic", "class", "view", new ApplicationType("type"), params.asJava)
+
+  def newFakeExecutorSummary(
+    id: String,
+    totalGCTime: Long,
+    totalDuration: Long
+  ): ExecutorSummaryImpl = new ExecutorSummaryImpl(
+    id,
+    hostPort = "",
+    rddBlocks = 0,
+    memoryUsed=0,
+    diskUsed = 0,
+    activeTasks = 0,
+    failedTasks = 0,
+    completedTasks = 0,
+    totalTasks = 0,
+    totalDuration,
+    totalInputBytes=0,
+    totalShuffleRead=0,
+    totalShuffleWrite= 0,
+    maxMemory= 0,
+    totalGCTime,
+    executorLogs = Map.empty
+  )
+
+  def newFakeSparkApplicationData(
+    executorSummaries: Seq[ExecutorSummaryImpl]
+  ): SparkApplicationData = {
+    val appId = "application_1"
+
+    val restDerivedData = SparkRestDerivedData(
+      new ApplicationInfoImpl(appId, name = "app", Seq.empty),
+      jobDatas = Seq.empty,
+      stageDatas = Seq.empty,
+      executorSummaries = executorSummaries
+    )
+    SparkApplicationData(appId, restDerivedData, None)
+  }
+}

test/com/linkedin/drelephant/spark/heuristics/ExecutorsHeuristicTest.scala

@@ -249,6 +249,7 @@ object ExecutorsHeuristicTest {
     totalShuffleRead,
     totalShuffleWrite,
     maxMemory,
+    totalGCTime = 0,
     executorLogs = Map.empty
   )