YARN-11809. Support application backoff mechanism for CapacityScheduler.

Author: TaoYang526

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/SchedulerApplicationAttempt.java

@@ -184,7 +184,16 @@ public class SchedulerApplicationAttempt implements SchedulableEntity {
   private ConcurrentHashMultiset<SchedulerRequestKey>
       missedNonPartitionedReqSchedulingOpportunity =
       ConcurrentHashMultiset.create();
-  
+
+  /**
+   * Tracks the total number of times the application has missed scheduling
+   * opportunities, which will be incremented when the scheduler cannot allocate
+   * resources for the application, and reset to 0 when the scheduler
+   * successfully allocates resources for the application or transitions
+   * the application to the backoff state.
+   */
+  private final AtomicLong appMissedSchedulingOpportunities = new AtomicLong();
+
   // Time of the last container scheduled at the current allowed level
   protected Map<SchedulerRequestKey, Long> lastScheduledContainer =
       new ConcurrentHashMap<>();
@@ -1106,6 +1115,18 @@ void setSchedulingOpportunities(SchedulerRequestKey schedulerKey, int count) {
     schedulingOpportunities.setCount(schedulerKey, count);
   }
 
+  public void addAppMissedSchedulingOpportunities() {
+    appMissedSchedulingOpportunities.incrementAndGet();
+  }
+
+  public void resetAppMissedSchedulingOpportunities() {
+    appMissedSchedulingOpportunities.set(0);
+  }
+
+  public long getAppMissedSchedulingOpportunities() {
+    return appMissedSchedulingOpportunities.get();
+  }
+
   private AggregateAppResourceUsage getRunningAggregateAppResourceUsage() {
     long currentTimeMillis = System.currentTimeMillis();
     // Don't walk the whole container list if the resources were computed

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/activities/ActivityDiagnosticConstant.java

@@ -70,6 +70,9 @@ public class ActivityDiagnosticConstant {
   public final static String APPLICATION_DO_NOT_NEED_RESOURCE =
       "Application does not need more resource";
 
+  public static final String APPLICATION_IN_BACKOFF_STATE =
+      "Application is in backoff state due to reaching missed scheduling threshold";
+
   /*
    * Request level diagnostics
    */

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/AbstractLeafQueue.java

@@ -31,6 +31,7 @@
 import java.util.TreeSet;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.TimeUnit;
 import java.util.stream.Stream;
 
 import org.apache.commons.lang3.StringUtils;
@@ -39,6 +40,8 @@
 import org.apache.hadoop.security.AccessControlException;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.security.authorize.AccessControlList;
+import org.apache.hadoop.thirdparty.com.google.common.cache.Cache;
+import org.apache.hadoop.thirdparty.com.google.common.cache.CacheBuilder;
 import org.apache.hadoop.util.Sets;
 import org.apache.hadoop.util.Time;
 import org.apache.hadoop.yarn.api.records.ApplicationAttemptId;
@@ -154,6 +157,13 @@ public class AbstractLeafQueue extends AbstractCSQueue {
   private final List<FiCaSchedulerApp> runnableApps = new ArrayList<>();
   private final List<FiCaSchedulerApp> nonRunnableApps = new ArrayList<>();
 
+  // Backoff related variables
+  private final boolean appBackoffEnabled;
+  private long appBackoffIntervalMs = 0L;
+  private long appBackoffMissedThreshold = 0L;
+  // Cache of applications that are in backoff state
+  private Cache<ApplicationId, Boolean> appsInBackoffState = null;
+
   public AbstractLeafQueue(CapacitySchedulerQueueContext queueContext,
       String queueName, CSQueue parent, CSQueue old) throws IOException {
     this(queueContext, queueName, parent, old, false);
@@ -170,6 +180,26 @@ public AbstractLeafQueue(CapacitySchedulerQueueContext queueContext,
 
     // One time initialization is enough since it is static ordering policy
     this.pendingOrderingPolicy = new FifoOrderingPolicyForPendingApps<>();
+
+    // Initialize the backoff configurations
+    CapacitySchedulerConfiguration conf = queueContext.getConfiguration();
+    appBackoffEnabled = conf.isAppBackoffEnabled(queuePath);
+    if (appBackoffEnabled) {
+      appBackoffIntervalMs = conf.getAppBackoffIntervalMs(queuePath);
+      if (appBackoffIntervalMs <= 0) {
+        throw new IOException(
+            "Backoff interval must be greater than 0 for queue: " + queuePath);
+      }
+      appBackoffMissedThreshold =
+          conf.getAppBackoffMissedThreshold(queuePath);
+      if (appBackoffMissedThreshold <= 0) {
+        throw new IOException(
+            "Backoff app missed threshold must be greater than 0 for queue: "
+                + queuePath);
+      }
+      appsInBackoffState = CacheBuilder.newBuilder().expireAfterAccess(
+          appBackoffIntervalMs, TimeUnit.MILLISECONDS).build();
+    }
   }
 
   @SuppressWarnings("checkstyle:nowhitespaceafter")
@@ -314,7 +344,10 @@ protected void setupQueueConfigs(Resource clusterResource) throws
               + defaultAppPriorityPerQueue + "\npriority = " + priority
               + "\nmaxLifetime = " + getMaximumApplicationLifetime()
               + " seconds" + "\ndefaultLifetime = "
-              + getDefaultApplicationLifetime() + " seconds");
+              + getDefaultApplicationLifetime() + " seconds"
+              + "\nbackoffEnabled = " + appBackoffEnabled
+              + "\nbackoffIntervalMs = " + appBackoffIntervalMs
+              + "\nbackoffAppMissedThreshold = " + appBackoffMissedThreshold);
     } finally {
       writeLock.unlock();
     }
@@ -1212,6 +1245,33 @@ public CSAssignment assignContainers(Resource clusterResource,
          assignmentIterator.hasNext();) {
       FiCaSchedulerApp application = assignmentIterator.next();
 
+      // Check for backoff state
+      if (isAppInBackoffState(application.getApplicationId())) {
+        // Skip if this app is still in backoff state
+        ActivitiesLogger.APP.recordRejectedAppActivityFromLeafQueue(
+            activitiesManager, node, application, application.getPriority(),
+            ActivityDiagnosticConstant.APPLICATION_IN_BACKOFF_STATE);
+        continue;
+      }
+
+      // Check for missed scheduling opportunities
+      if (isAppShouldEnterBackoffState(application)) {
+        // Don't assign containers to this app when the missed opportunities reached the threshold.
+        LOG.info("Skip scheduling for application {} as it has reached the "
+            + "missed scheduling threshold {}, the backoff interval is {} ms.",
+            application.getApplicationId(), appBackoffMissedThreshold,
+            appBackoffIntervalMs);
+        ActivitiesLogger.APP.recordRejectedAppActivityFromLeafQueue(
+            activitiesManager, node, application, application.getPriority(),
+            ActivityDiagnosticConstant.APPLICATION_IN_BACKOFF_STATE);
+        // Add the app to the backoff state, to prevent further scheduling
+        // attempts during the backoff period.
+        appsInBackoffState.put(application.getApplicationId(), true);
+        // Reset missed scheduling opportunities
+        application.resetAppMissedSchedulingOpportunities();
+        continue;
+      }
+
       ActivitiesLogger.APP.startAppAllocationRecording(activitiesManager,
           node, SystemClock.getInstance().getTime(), application);
 
@@ -1302,19 +1362,26 @@ public CSAssignment assignContainers(Resource clusterResource,
         ActivitiesLogger.QUEUE.recordQueueActivity(activitiesManager, node,
             parent.getQueuePath(), getQueuePath(),
             ActivityState.ACCEPTED, ActivityDiagnosticConstant.EMPTY);
+        // Reset missed scheduling opportunities after successfully allocating
+        // resources for the application.
+        application.resetAppMissedSchedulingOpportunities();
         return assignment;
       } else if (assignment.getSkippedType()
           == CSAssignment.SkippedType.OTHER) {
         ActivitiesLogger.APP.finishSkippedAppAllocationRecording(
             activitiesManager, application.getApplicationId(),
             ActivityState.SKIPPED, ActivityDiagnosticConstant.EMPTY);
         application.updateNodeInfoForAMDiagnostics(node);
+        // Add missed scheduling opportunities for the application
+        application.addAppMissedSchedulingOpportunities();
       } else if (assignment.getSkippedType()
           == CSAssignment.SkippedType.QUEUE_LIMIT) {
         ActivitiesLogger.QUEUE.recordQueueActivity(activitiesManager, node,
             parent.getQueuePath(), getQueuePath(), ActivityState.REJECTED,
             () -> ActivityDiagnosticConstant.QUEUE_DO_NOT_HAVE_ENOUGH_HEADROOM
                 + " from " + application.getApplicationId());
+        // Add missed scheduling opportunities for the application
+        application.addAppMissedSchedulingOpportunities();
         return assignment;
       } else{
         // If we don't allocate anything, and it is not skipped by application,
@@ -1335,6 +1402,15 @@ public CSAssignment assignContainers(Resource clusterResource,
     return CSAssignment.NULL_ASSIGNMENT;
   }
 
+  public boolean isAppInBackoffState(ApplicationId appId) {
+    return appBackoffEnabled && appsInBackoffState.getIfPresent(appId) != null;
+  }
+
+  public boolean isAppShouldEnterBackoffState(FiCaSchedulerApp application) {
+    return appBackoffEnabled &&
+        application.getAppMissedSchedulingOpportunities() >= appBackoffMissedThreshold;
+  }
+
   @Override
   public boolean accept(Resource cluster,
       ResourceCommitRequest<FiCaSchedulerApp, FiCaSchedulerNode> request) {

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/CapacitySchedulerConfiguration.java

@@ -76,6 +76,7 @@
 import java.util.Set;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
+import java.util.concurrent.TimeUnit;
 
 import static org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.QueuePrefixes.getAutoCreatedQueueObjectTemplateConfPrefix;
 import static org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.QueuePrefixes.getNodeLabelPrefix;
@@ -3036,4 +3037,131 @@ private String normalizePolicyName(String policyName) {
           "Could not instantiate " + "NodesSortingPolicy: " + policyName, e);
     }
   }
+
+  /**
+   * Configuration keys for enabling backoff mechanism for a queue.
+   * When enabled, applications in the queue will be temporarily skipped
+   * if they fail to schedule tasks after a certain number of opportunities.
+   */
+  @Private
+  public static final String BACKOFF_ENABLED = "app-backoff.enabled";
+
+  /**
+   * Default value for enabling backoff mechanism.
+   */
+  @Private
+  public static final boolean DEFAULT_BACKOFF_ENABLED = false;
+
+  /**
+   * Configuration key indicating the duration for which an application
+   * in backoff state will be skipped during the scheduling process.
+   */
+  @Private
+  public static final String APP_BACKOFF_INTERVAL_MS = "app-backoff.interval-ms";
+
+  /**
+   * Default value for the backoff duration in milliseconds.
+   */
+  @Private
+  public static final long DEFAULT_APP_BACKOFF_INTERVAL_MS = 3000L;
+
+  /**
+   * Configuration key for the threshold of missed scheduling opportunities
+   * before an application is put into backoff state.
+   */
+  @Private
+  public static final String APP_BACKOFF_MISSED_THRESHOLD =
+      "app-backoff.missed-threshold";
+
+  /**
+   * Default value for missed opportunities' threshold.
+   */
+  @Private
+  public static final long DEFAULT_APP_BACKOFF_MISSED_THRESHOLD = 3L;
+
+  /**
+   * Get the global default value for backoff enabled setting.
+   * @return true if backoff is enabled, false otherwise
+   */
+  public boolean getGlobalAppBackoffEnabled() {
+    return getBoolean(PREFIX + BACKOFF_ENABLED, DEFAULT_BACKOFF_ENABLED);
+  }
+
+  /**
+   * Get the global default value for backoff interval in milliseconds.
+   * @return the backoff interval in milliseconds
+   */
+  public long getGlobalAppBackoffIntervalMs() {
+    return getTimeDuration(PREFIX + APP_BACKOFF_INTERVAL_MS,
+        DEFAULT_APP_BACKOFF_INTERVAL_MS, TimeUnit.MILLISECONDS);
+  }
+
+  /**
+   * Get the global default value for missed opportunities' threshold.
+   * @return the missed opportunities threshold
+   */
+  public long getGlobalAppBackoffMissedThreshold() {
+    return getLong(PREFIX + APP_BACKOFF_MISSED_THRESHOLD,
+        DEFAULT_APP_BACKOFF_MISSED_THRESHOLD);
+  }
+
+  /**
+   * Check if app-backoff is enabled for a specific queue.
+   * @param queue the queue path
+   * @return true if app-backoff is enabled for the queue, false otherwise
+   */
+  public boolean isAppBackoffEnabled(QueuePath queue) {
+    return getBoolean(getQueuePrefix(queue) + BACKOFF_ENABLED,
+        getGlobalAppBackoffEnabled());
+  }
+
+  /**
+   * Get the app-backoff interval in milliseconds for a specific queue.
+   * @param queue the queue path
+   * @return the app-backoff interval in milliseconds
+   */
+  public long getAppBackoffIntervalMs(QueuePath queue) {
+    return getTimeDuration(getQueuePrefix(queue) + APP_BACKOFF_INTERVAL_MS,
+        getGlobalAppBackoffIntervalMs(), TimeUnit.MILLISECONDS);
+  }
+
+  /**
+   * Get the missed opportunities threshold for a specific queue.
+   * @param queue the queue path
+   * @return the missed opportunities threshold
+   */
+  public long getAppBackoffMissedThreshold(QueuePath queue) {
+    return getLong(getQueuePrefix(queue) + APP_BACKOFF_MISSED_THRESHOLD,
+        getGlobalAppBackoffMissedThreshold());
+  }
+
+  /**
+   * Set the app-backoff enabled flag for a specific queue (for testing).
+   * @param queue the queue path
+   * @param enabled the backoff enabled flag
+   */
+  @VisibleForTesting
+  public void setAppBackoffEnabled(QueuePath queue, boolean enabled) {
+    setBoolean(getQueuePrefix(queue) + BACKOFF_ENABLED, enabled);
+  }
+
+  /**
+   * Set the app-backoff interval in milliseconds for a specific queue (for testing).
+   * @param queue the queue path
+   * @param intervalMs the backoff interval in milliseconds
+   */
+  @VisibleForTesting
+  public void setAppBackoffIntervalMs(QueuePath queue, long intervalMs) {
+    setLong(getQueuePrefix(queue) + APP_BACKOFF_INTERVAL_MS, intervalMs);
+  }
+
+  /**
+   * Set the app-backoff missed opportunities threshold for a specific queue (for testing).
+   * @param queue the queue path
+   * @param threshold the missed opportunities threshold
+   */
+  @VisibleForTesting
+  public void setAppBackoffMissedThreshold(QueuePath queue, long threshold) {
+    setLong(getQueuePrefix(queue) + APP_BACKOFF_MISSED_THRESHOLD, threshold);
+  }
 }