From 4eda58c13641c14c4b248843a2589781cbcd343f Mon Sep 17 00:00:00 2001
From: Arun Suresh <asuresh@apache.org>
Date: Wed, 10 Jan 2018 09:04:30 -0800
Subject: [PATCH] YARN-7681. Double-check placement constraints in scheduling
 phase before actual allocation is made. (Weiwei Yang via asuresh)

---
 .../scheduler/capacity/CapacityScheduler.java | 23 +++++++++++++++++++
 1 file changed, 23 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 e682d0fc84..d2713c8fbe 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
@@ -124,6 +124,8 @@
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.common.SchedulerContainer;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.common.fica.FiCaSchedulerApp;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.common.fica.FiCaSchedulerNode;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.constraint.InvalidAllocationTagsQueryException;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.constraint.PlacementConstraintsUtil;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.AppAddedSchedulerEvent;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.AppAttemptAddedSchedulerEvent;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.event.AppAttemptRemovedSchedulerEvent;
@@ -2574,6 +2576,27 @@ public boolean attemptAllocationOnNode(SchedulerApplicationAttempt appAttempt,
         ResourceCommitRequest<FiCaSchedulerApp, FiCaSchedulerNode>
             resourceCommitRequest = createResourceCommitRequest(
             appAttempt, schedulingRequest, schedulerNode);
+
+        // Validate placement constraint is satisfied before
+        // committing the request.
+        try {
+          if (!PlacementConstraintsUtil.canSatisfyConstraints(
+              appAttempt.getApplicationId(),
+              schedulingRequest.getAllocationTags(),
+              schedulerNode,
+              rmContext.getPlacementConstraintManager(),
+              rmContext.getAllocationTagsManager())) {
+            LOG.debug("Failed to allocate container for application "
+                + appAttempt.getApplicationId() + " on node "
+                + schedulerNode.getNodeName()
+                + " because this allocation violates the"
+                + " placement constraint.");
+            return false;
+          }
+        } catch (InvalidAllocationTagsQueryException e) {
+          LOG.warn("Unable to allocate container", e);
+          return false;
+        }
         return tryCommit(getClusterResource(), resourceCommitRequest, false);
       }
     }