From 9688c84879ef9c5f98d06e08944c65b193edcc44 Mon Sep 17 00:00:00 2001
From: Mingkang Li <mingkang.li@databricks.com>
Date: Wed, 17 Jul 2024 10:56:31 -0700
Subject: [PATCH] add warning message

---
 core/src/main/scala/org/apache/spark/rdd/RDD.scala | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/core/src/main/scala/org/apache/spark/rdd/RDD.scala b/core/src/main/scala/org/apache/spark/rdd/RDD.scala
index ac93abf3fe7a..0db0133f632b 100644
--- a/core/src/main/scala/org/apache/spark/rdd/RDD.scala
+++ b/core/src/main/scala/org/apache/spark/rdd/RDD.scala
@@ -211,6 +211,11 @@ abstract class RDD[T: ClassTag](
    * @return This RDD.
    */
   def unpersist(blocking: Boolean = false): this.type = {
+    if (isLocallyCheckpointed) {
+      // This means its lineage has been truncated and cannot be recomputed once unpersisted.
+      logWarning(log"RDD ${MDC(RDD_ID, id)} was locally checkpointed, its lineage has been" +
+        log" truncated and cannot be recomputed after unpersisting")
+    }
     logInfo(log"Removing RDD ${MDC(RDD_ID, id)} from persistence list")
     sc.unpersistRDD(id, blocking)
     storageLevel = StorageLevel.NONE