YARN-6428. Queue AM limit is not honored in CS always. Contributed by Bibin A Chundatt.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/util/resource/DominantResourceCalculator.java

@@ -218,27 +218,19 @@ public class DominantResourceCalculator extends ResourceCalculator {
   public Resource multiplyAndNormalizeUp(Resource r, double by,
       Resource stepFactor) {
     return Resources.createResource(
-        roundUp(
-            (int)Math.ceil(r.getMemorySize() * by), stepFactor.getMemorySize()),
-        roundUp(
-            (int)Math.ceil(r.getVirtualCores() * by),
-            stepFactor.getVirtualCores())
-        );
+        roundUp((long) Math.ceil((float) (r.getMemorySize() * by)),
+            stepFactor.getMemorySize()),
+        roundUp((int) Math.ceil((float) (r.getVirtualCores() * by)),
+            stepFactor.getVirtualCores()));
   }
 
   @Override
   public Resource multiplyAndNormalizeDown(Resource r, double by,
       Resource stepFactor) {
     return Resources.createResource(
-        roundDown(
-            (int)(r.getMemorySize() * by),
-            stepFactor.getMemorySize()
-            ),
-        roundDown(
-            (int)(r.getVirtualCores() * by),
-            stepFactor.getVirtualCores()
-            )
-        );
+        roundDown((long) (r.getMemorySize() * by), stepFactor.getMemorySize()),
+        roundDown((int) (r.getVirtualCores() * by),
+            stepFactor.getVirtualCores()));
   }
 
   @Override

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/TestCapacityScheduler.java

@@ -4417,4 +4417,44 @@ public class TestCapacityScheduler {
     Assert.assertEquals(b1.getState(), QueueState.RUNNING);
     Assert.assertTrue(!b1.getChildQueues().isEmpty());
   }
+
+  @Test(timeout = 30000)
+  public void testAMLimitDouble() throws Exception {
+    CapacitySchedulerConfiguration config =
+        new CapacitySchedulerConfiguration();
+    config.set(CapacitySchedulerConfiguration.RESOURCE_CALCULATOR_CLASS,
+        DominantResourceCalculator.class.getName());
+    CapacitySchedulerConfiguration conf =
+        new CapacitySchedulerConfiguration(config);
+    conf.setClass(YarnConfiguration.RM_SCHEDULER, CapacityScheduler.class,
+        ResourceScheduler.class);
+    conf.setInt("yarn.scheduler.minimum-allocation-mb", 512);
+    conf.setInt("yarn.scheduler.minimum-allocation-vcores", 1);
+    MockRM rm = new MockRM(conf);
+    rm.start();
+    rm.registerNode("127.0.0.1:1234", 10 * GB);
+    rm.registerNode("127.0.0.1:1235", 10 * GB);
+    rm.registerNode("127.0.0.1:1236", 10 * GB);
+    rm.registerNode("127.0.0.1:1237", 10 * GB);
+    ResourceScheduler scheduler = rm.getRMContext().getScheduler();
+    waitforNMRegistered(scheduler, 4, 5);
+    LeafQueue queueA =
+        (LeafQueue) ((CapacityScheduler) scheduler).getQueue("default");
+    Resource amResourceLimit = queueA.getAMResourceLimit();
+    Assert.assertEquals(4096, amResourceLimit.getMemorySize());
+    Assert.assertEquals(4, amResourceLimit.getVirtualCores());
+    rm.stop();
+  }
+
+  private void waitforNMRegistered(ResourceScheduler scheduler, int nodecount,
+      int timesec) throws InterruptedException {
+    long start = System.currentTimeMillis();
+    while (System.currentTimeMillis() - start < timesec * 1000) {
+      if (scheduler.getNumClusterNodes() < nodecount) {
+        Thread.sleep(100);
+      } else {
+        break;
+      }
+    }
+  }
 }