HDFS-17713. [ARR] Throtting asynchronous calls for each nameservice.

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/fairness/RouterAsyncRpcFairnessPolicyController.java

@@ -0,0 +1,66 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.hdfs.server.federation.fairness;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hdfs.server.federation.router.FederationUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.Set;
+
+import static org.apache.hadoop.hdfs.server.federation.router.RBFConfigKeys.
+    DFS_ROUTER_ASYNC_RPC_MAX_ASYNCCALL_PERMIT_KEY;
+import static org.apache.hadoop.hdfs.server.federation.router.RBFConfigKeys.
+    DFS_ROUTER_ASYNC_RPC_MAX_ASYNC_CALL_PERMIT_DEFAULT;
+
+public class RouterAsyncRpcFairnessPolicyController extends
+    AbstractRouterRpcFairnessPolicyController {
+
+  private static final Logger LOG =
+      LoggerFactory.getLogger(RouterAsyncRpcFairnessPolicyController.class);
+
+  public RouterAsyncRpcFairnessPolicyController(Configuration conf) {
+    init(conf);
+  }
+
+  public void init(Configuration conf) throws IllegalArgumentException {
+    super.init(conf);
+
+    int maxAsyncCallPermit = conf.getInt(DFS_ROUTER_ASYNC_RPC_MAX_ASYNCCALL_PERMIT_KEY,
+        DFS_ROUTER_ASYNC_RPC_MAX_ASYNC_CALL_PERMIT_DEFAULT);
+    if (maxAsyncCallPermit <= 0) {
+      maxAsyncCallPermit = DFS_ROUTER_ASYNC_RPC_MAX_ASYNC_CALL_PERMIT_DEFAULT;
+    }
+    LOG.info("Max async call permits per nameservice: {}", maxAsyncCallPermit);
+
+    // Get all name services configured
+    Set<String> allConfiguredNS = FederationUtil.getAllConfiguredNS(conf);
+
+    for (String nsId : allConfiguredNS) {
+      LOG.info("Dedicated permits {} for ns {} ", maxAsyncCallPermit, nsId);
+      insertNameServiceWithPermits(nsId, maxAsyncCallPermit);
+      logAssignment(nsId, maxAsyncCallPermit);
+    }
+  }
+
+  private static void logAssignment(String nsId, int count) {
+    LOG.info("Assigned {} permits to nsId {} ", count, nsId);
+  }
+}

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RBFConfigKeys.java

@@ -88,6 +88,9 @@ public class RBFConfigKeys extends CommonConfigurationKeysPublic {
   public static final String DFS_ROUTER_ASYNC_RPC_RESPONDER_COUNT_KEY =
           FEDERATION_ROUTER_ASYNC_RPC_PREFIX + "responder.count";
   public static final int DFS_ROUTER_ASYNCRPC_RESPONDER_COUNT_DEFAULT = 10;
+  public static final String DFS_ROUTER_ASYNC_RPC_MAX_ASYNCCALL_PERMIT_KEY =
+      FEDERATION_ROUTER_ASYNC_RPC_PREFIX + "max.asynccall.permit";
+  public static final int DFS_ROUTER_ASYNC_RPC_MAX_ASYNC_CALL_PERMIT_DEFAULT = 20000;
 
   public static final String DFS_ROUTER_METRICS_ENABLE =
       FEDERATION_ROUTER_PREFIX + "metrics.enable";

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterRpcClient.java

@@ -1880,7 +1880,7 @@ protected void releasePermit(final String nsId, final UserGroupInformation ugi,
     return routerRpcFairnessPolicyController;
   }
 
-  private void incrRejectedPermitForNs(String ns) {
+  protected void incrRejectedPermitForNs(String ns) {
     rejectedPermitsPerNs.computeIfAbsent(ns, k -> new LongAdder()).increment();
   }
 
@@ -1889,7 +1889,7 @@ public Long getRejectedPermitForNs(String ns) {
         rejectedPermitsPerNs.get(ns).longValue() : 0L;
   }
 
-  private void incrAcceptedPermitForNs(String ns) {
+  protected void incrAcceptedPermitForNs(String ns) {
     acceptedPermitsPerNs.computeIfAbsent(ns, k -> new LongAdder()).increment();
   }