From f5345b881d9d52e4eb932baa0b9ad8325a2c261f Mon Sep 17 00:00:00 2001
From: "gavin.wang" <gracejianbo@163.com>
Date: Mon, 23 Sep 2024 15:39:15 +0800
Subject: [PATCH] YARN-11560. Fix NPE bug when multi-node enabled with schedule
 asynchronously (#6021). Contributed by wangzhongwei.

---
 .../resourcemanager/scheduler/capacity/CapacityScheduler.java | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/CapacityScheduler.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/CapacityScheduler.java
index ec5b074915..d4eff239ff 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/CapacityScheduler.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/CapacityScheduler.java
@@ -1737,6 +1737,10 @@ private CSAssignment allocateContainerOnSingleNode(
 
   private void allocateFromReservedContainer(FiCaSchedulerNode node,
       boolean withNodeHeartbeat, RMContainer reservedContainer) {
+    if(reservedContainer == null){
+      LOG.warn("reservedContainer is null, that may be unreserved by the proposal judgment thread");
+      return;
+    }
     FiCaSchedulerApp reservedApplication = getCurrentAttemptForContainer(
         reservedContainer.getContainerId());
     if (reservedApplication == null) {