diff --git a/app/com/linkedin/drelephant/spark/fetchers/SparkFetcher.scala b/app/com/linkedin/drelephant/spark/fetchers/SparkFetcher.scala
index e3ea982c1..d9913851b 100644
--- a/app/com/linkedin/drelephant/spark/fetchers/SparkFetcher.scala
+++ b/app/com/linkedin/drelephant/spark/fetchers/SparkFetcher.scala
@@ -18,7 +18,7 @@ package com.linkedin.drelephant.spark.fetchers
 
 import java.util.concurrent.TimeoutException
 
-import scala.concurrent.{Await, ExecutionContext, Future, blocking}
+import scala.concurrent.{Await, ExecutionContext, Future}
 import scala.concurrent.duration.{Duration, SECONDS}
 import scala.util.{Failure, Success, Try}
 import com.linkedin.drelephant.analysis.{AnalyticJob, ElephantFetcher}
@@ -110,22 +110,20 @@ class SparkFetcher(fetcherConfigurationData: FetcherConfigurationData)
   }
 
   private def doFetchDataUsingRestAndLogClients(analyticJob: AnalyticJob): Future[SparkApplicationData] = Future {
-    blocking {
-      val appId = analyticJob.getAppId
-      val restDerivedData = Await.result(sparkRestClient.fetchData(appId, eventLogSource == EventLogSource.Rest), DEFAULT_TIMEOUT)
-
-      val logDerivedData = eventLogSource match {
-        case EventLogSource.None => None
-        case EventLogSource.Rest => restDerivedData.logDerivedData
-        case EventLogSource.WebHdfs =>
-          val lastAttemptId = restDerivedData.applicationInfo.attempts.maxBy {
-            _.startTime
-          }.attemptId
-          Some(Await.result(sparkLogClient.fetchData(appId, lastAttemptId), DEFAULT_TIMEOUT))
-      }
-
-      SparkApplicationData(appId, restDerivedData, logDerivedData)
+    val appId = analyticJob.getAppId
+    val restDerivedData = Await.result(sparkRestClient.fetchData(appId, eventLogSource == EventLogSource.Rest), DEFAULT_TIMEOUT)
+
+    val logDerivedData = eventLogSource match {
+      case EventLogSource.None => None
+      case EventLogSource.Rest => restDerivedData.logDerivedData
+      case EventLogSource.WebHdfs =>
+        val lastAttemptId = restDerivedData.applicationInfo.attempts.maxBy {
+          _.startTime
+        }.attemptId
+        Some(Await.result(sparkLogClient.fetchData(appId, lastAttemptId), DEFAULT_TIMEOUT))
     }
+    SparkApplicationData(appId, restDerivedData, logDerivedData)
+
   }
 
 }
@@ -135,12 +133,16 @@ object SparkFetcher {
   sealed trait EventLogSource
 
   object EventLogSource {
+
     /** Fetch event logs through REST API. */
     case object Rest extends EventLogSource
+
     /** Fetch event logs through WebHDFS. */
     case object WebHdfs extends EventLogSource
+
     /** Event logs are not available. */
     case object None extends EventLogSource
+
   }
 
   val SPARK_EVENT_LOG_ENABLED_KEY = "spark.eventLog.enabled"
diff --git a/app/com/linkedin/drelephant/spark/fetchers/SparkLogClient.scala b/app/com/linkedin/drelephant/spark/fetchers/SparkLogClient.scala
index 2bdefa15c..71023fab4 100644
--- a/app/com/linkedin/drelephant/spark/fetchers/SparkLogClient.scala
+++ b/app/com/linkedin/drelephant/spark/fetchers/SparkLogClient.scala
@@ -19,7 +19,7 @@ package com.linkedin.drelephant.spark.fetchers
 import java.io.InputStream
 import java.security.PrivilegedAction
 
-import scala.concurrent.{ExecutionContext, Future, blocking}
+import scala.concurrent.{ExecutionContext, Future}
 import scala.io.Source
 
 import com.linkedin.drelephant.security.HadoopSecurity
@@ -62,9 +62,8 @@ class SparkLogClient(hadoopConfiguration: Configuration, sparkConf: SparkConf, e
     val (eventLogPath, eventLogCodec) =
       sparkUtils.pathAndCodecforEventLog(sparkConf, eventLogFileSystem, baseEventLogPath, appId, attemptId)
 
-    Future { blocking {
+    Future { 
         sparkUtils.withEventLog(eventLogFileSystem, eventLogPath, eventLogCodec)(findDerivedData(_))
-      }
     }
   }
 }
diff --git a/app/com/linkedin/drelephant/spark/fetchers/SparkRestClient.scala b/app/com/linkedin/drelephant/spark/fetchers/SparkRestClient.scala
index 5f222e5d8..419c0bb39 100644
--- a/app/com/linkedin/drelephant/spark/fetchers/SparkRestClient.scala
+++ b/app/com/linkedin/drelephant/spark/fetchers/SparkRestClient.scala
@@ -25,7 +25,7 @@ import java.util.{Calendar, SimpleTimeZone}
 import com.linkedin.drelephant.spark.legacydata.LegacyDataConverters
 import org.apache.spark.deploy.history.SparkDataCollection
 
-import scala.concurrent.{Await, ExecutionContext, Future, blocking}
+import scala.concurrent.{Await, ExecutionContext, Future}
 import scala.util.control.NonFatal
 import com.fasterxml.jackson.databind.{DeserializationFeature, ObjectMapper}
 import com.fasterxml.jackson.module.scala.DefaultScalaModule
@@ -81,53 +81,40 @@ class SparkRestClient(sparkConf: SparkConf) {
     val (applicationInfo, attemptTarget) = getApplicationMetaData(appId)
 
     Future {
-      blocking {
-        val futureJobDatas = Future {
-          blocking {
-            getJobDatas(attemptTarget)
-          }
-        }
-        val futureStageDatas = Future {
-          blocking {
-            getStageDatas(attemptTarget)
-          }
-        }
-        val futureExecutorSummaries = Future {
-          blocking {
-            getExecutorSummaries(attemptTarget)
-          }
+      val futureJobDatas = Future {
+        getJobDatas(attemptTarget)
+      }
+      val futureStageDatas = Future {
+        getStageDatas(attemptTarget)
+      }
+      val futureExecutorSummaries = Future {
+        getExecutorSummaries(attemptTarget)
+      }
+      val futureLogData = if (fetchLogs) {
+        Future {
+          getLogData(attemptTarget)
         }
-        val futureLogData = if (fetchLogs) {
-          Future {
-            blocking {
-              getLogData(attemptTarget)
-            }
-          }
-        } else Future.successful(None)
-
-        if (fetchFailedTasks) {
-          val futureFailedTasksDatas = Future {
-            blocking {
-              getStagesWithFailedTasks(attemptTarget)
-            }
-          }
-          SparkRestDerivedData(
-            applicationInfo,
-            Await.result(futureJobDatas, DEFAULT_TIMEOUT),
-            Await.result(futureStageDatas, DEFAULT_TIMEOUT),
-            Await.result(futureExecutorSummaries, DEFAULT_TIMEOUT),
-            Await.result(futureFailedTasksDatas, DEFAULT_TIMEOUT),
-            Await.result(futureLogData, DEFAULT_TIMEOUT))
-        } else {
-          SparkRestDerivedData(
-            applicationInfo,
-            Await.result(futureJobDatas, DEFAULT_TIMEOUT),
-            Await.result(futureStageDatas, DEFAULT_TIMEOUT),
-            Await.result(futureExecutorSummaries, DEFAULT_TIMEOUT),
-            Seq.empty,
-            Await.result(futureLogData, DEFAULT_TIMEOUT)
-          )
+      } else Future.successful(None)
+      if (fetchFailedTasks) {
+        val futureFailedTasksDatas = Future {
+          getStagesWithFailedTasks(attemptTarget)
         }
+        SparkRestDerivedData(
+          applicationInfo,
+          Await.result(futureJobDatas, DEFAULT_TIMEOUT),
+          Await.result(futureStageDatas, DEFAULT_TIMEOUT),
+          Await.result(futureExecutorSummaries, DEFAULT_TIMEOUT),
+          Await.result(futureFailedTasksDatas, DEFAULT_TIMEOUT),
+          Await.result(futureLogData, DEFAULT_TIMEOUT))
+      } else {
+        SparkRestDerivedData(
+          applicationInfo,
+          Await.result(futureJobDatas, DEFAULT_TIMEOUT),
+          Await.result(futureStageDatas, DEFAULT_TIMEOUT),
+          Await.result(futureExecutorSummaries, DEFAULT_TIMEOUT),
+          Seq.empty,
+          Await.result(futureLogData, DEFAULT_TIMEOUT)
+        )
       }
     }
   }