Improve comment in block manager and the master endpoint

apache · Nov 16, 2023 · 5480faa · 5480faa
1 parent 6d002a3
commit 5480faa
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Showing 2 changed files with 5 additions and 2 deletions.
diff --git a/core/src/main/scala/org/apache/spark/storage/BlockManager.scala b/core/src/main/scala/org/apache/spark/storage/BlockManager.scala
@@ -193,8 +193,8 @@ private[spark] class BlockManager(
   extends BlockDataManager with BlockEvictionHandler with Logging {
 
   // We initialize the ShuffleManager later in SparkContext and Executor, to allow
-  // user jars to define custom ShuffleManagers, as such `_shuffleManager` will be null for the
-  // executor, and we ask for the instance from the SparkEnv.
+  // user jars to define custom ShuffleManagers, as such `_shuffleManager` will be null here
+  // (except for tests) and we ask for the instance from the SparkEnv.
   private lazy val shuffleManager = Option(_shuffleManager).getOrElse(SparkEnv.get.shuffleManager)
 
   // same as `conf.get(config.SHUFFLE_SERVICE_ENABLED)`

diff --git a/core/src/main/scala/org/apache/spark/storage/BlockManagerMasterEndpoint.scala b/core/src/main/scala/org/apache/spark/storage/BlockManagerMasterEndpoint.scala
@@ -58,6 +58,9 @@ class BlockManagerMasterEndpoint(
     isDriver: Boolean)
   extends IsolatedThreadSafeRpcEndpoint with Logging {
 
+  // We initialize the ShuffleManager later in SparkContext and Executor, to allow
+  // user jars to define custom ShuffleManagers, as such `_shuffleManager` will be null here
+  // (except for tests) and we ask for the instance from the SparkEnv.
   private lazy val shuffleManager = Option(_shuffleManager).getOrElse(SparkEnv.get.shuffleManager)
 
   // Mapping from executor id to the block manager's local disk directories.