YARN-8482. [Router] Add cache for fast answers to getApps. (#4769)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/conf/YarnConfiguration.java

@@ -4128,6 +4128,15 @@ public static boolean isAclEnabled(Configuration conf) {
   public static final String ROUTER_KERBEROS_PRINCIPAL_HOSTNAME_KEY = ROUTER_PREFIX +
       "kerberos.principal.hostname";
 
+  /** Router enable AppsInfo Cache. **/
+  public static final String ROUTER_APPSINFO_ENABLED = ROUTER_WEBAPP_PREFIX + "appsinfo-enabled";
+  public static final boolean DEFAULT_ROUTER_APPSINFO_ENABLED = false;
+
+  /** Router AppsInfo Cache Count. **/
+  public static final String ROUTER_APPSINFO_CACHED_COUNT =
+      ROUTER_WEBAPP_PREFIX + "appsinfo-cached-count";
+  public static final int DEFAULT_ROUTER_APPSINFO_CACHED_COUNT = 100;
+
   ////////////////////////////////
   // CSI Volume configs
   ////////////////////////////////

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/resources/yarn-default.xml

@@ -4943,4 +4943,24 @@
     </description>
   </property>
 
+  <property>
+    <name>yarn.router.webapp.appsinfo-enabled</name>
+    <value>false</value>
+    <description>
+      This configuration is used to enable the cache of AppsInfo.
+      If it is set to true, the cache is enabled.
+      If it is set to false, the cache is not enabled.
+    </description>
+  </property>
+
+  <property>
+    <name>yarn.router.webapp.appsinfo-cached-count</name>
+    <value>100</value>
+    <description>
+      When yarn.router.appsinfo-enabled is set to true,
+      the number of cached appsInfo.
+      Default is 100
+    </description>
+  </property>
+
 </configuration>

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/webapp/FederationInterceptorREST.java

@@ -100,9 +100,11 @@
 import org.apache.hadoop.yarn.server.router.RouterMetrics;
 import org.apache.hadoop.yarn.server.router.RouterServerUtil;
 import org.apache.hadoop.yarn.server.router.clientrm.ClientMethod;
+import org.apache.hadoop.yarn.server.router.webapp.cache.RouterAppInfoCacheKey;
 import org.apache.hadoop.yarn.server.webapp.dao.AppAttemptInfo;
 import org.apache.hadoop.yarn.server.webapp.dao.ContainerInfo;
 import org.apache.hadoop.yarn.server.webapp.dao.ContainersInfo;
+import org.apache.hadoop.yarn.util.LRUCacheHashMap;
 import org.apache.hadoop.yarn.webapp.dao.SchedConfUpdateInfo;
 import org.apache.hadoop.yarn.util.Clock;
 import org.apache.hadoop.yarn.util.MonotonicClock;
@@ -132,8 +134,11 @@ public class FederationInterceptorREST extends AbstractRESTRequestInterceptor {
   private RouterMetrics routerMetrics;
   private final Clock clock = new MonotonicClock();
   private boolean returnPartialReport;
+  private boolean appInfosCacheEnabled;
+  private int appInfosCacheCount;
 
   private Map<SubClusterId, DefaultRequestInterceptorREST> interceptors;
+  private LRUCacheHashMap<RouterAppInfoCacheKey, AppsInfo> appInfosCaches;
 
   /**
    * Thread pool used for asynchronous operations.
@@ -170,6 +175,17 @@ public void init(String user) {
     returnPartialReport = conf.getBoolean(
         YarnConfiguration.ROUTER_WEBAPP_PARTIAL_RESULTS_ENABLED,
         YarnConfiguration.DEFAULT_ROUTER_WEBAPP_PARTIAL_RESULTS_ENABLED);
+
+    appInfosCacheEnabled = conf.getBoolean(
+        YarnConfiguration.ROUTER_APPSINFO_ENABLED,
+        YarnConfiguration.DEFAULT_ROUTER_APPSINFO_ENABLED);
+
+    if(appInfosCacheEnabled) {
+      appInfosCacheCount = conf.getInt(
+          YarnConfiguration.ROUTER_APPSINFO_CACHED_COUNT,
+          YarnConfiguration.DEFAULT_ROUTER_APPSINFO_CACHED_COUNT);
+      appInfosCaches = new LRUCacheHashMap<>(appInfosCacheCount, true);
+    }
   }
 
   private SubClusterId getRandomActiveSubCluster(
@@ -681,6 +697,18 @@ public AppsInfo getApps(HttpServletRequest hsr, String stateQuery,
       String queueQuery, String count, String startedBegin, String startedEnd,
       String finishBegin, String finishEnd, Set<String> applicationTypes,
       Set<String> applicationTags, String name, Set<String> unselectedFields) {
+
+    RouterAppInfoCacheKey routerAppInfoCacheKey = RouterAppInfoCacheKey.newInstance(
+        hsr, stateQuery, statesQuery, finalStatusQuery, userQuery, queueQuery, count,
+        startedBegin, startedEnd, finishBegin, finishEnd, applicationTypes,
+        applicationTags, name, unselectedFields);
+
+    if (appInfosCacheEnabled && routerAppInfoCacheKey != null) {
+      if (appInfosCaches.containsKey(routerAppInfoCacheKey)) {
+        return appInfosCaches.get(routerAppInfoCacheKey);
+      }
+    }
+
     AppsInfo apps = new AppsInfo();
     long startTime = clock.getTime();
 
@@ -744,8 +772,14 @@ public AppsInfo call() {
     }
 
     // Merge all the application reports got from all the available YARN RMs
-    return RouterWebServiceUtil.mergeAppsInfo(
+    AppsInfo resultAppsInfo = RouterWebServiceUtil.mergeAppsInfo(
         apps.getApps(), returnPartialReport);
+
+    if (appInfosCacheEnabled && routerAppInfoCacheKey != null) {
+      appInfosCaches.put(routerAppInfoCacheKey, resultAppsInfo);
+    }
+
+    return resultAppsInfo;
   }
 
   /**
@@ -1773,4 +1807,9 @@ private SubClusterInfo getHomeSubClusterInfoByAppId(String appId)
     }
     throw new YarnException("Unable to get subCluster by applicationId = " + appId);
   }
+
+  @VisibleForTesting
+  public LRUCacheHashMap<RouterAppInfoCacheKey, AppsInfo> getAppInfosCaches() {
+    return appInfosCaches;
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/webapp/cache/RouterAppInfoCacheKey.java

@@ -0,0 +1,156 @@
+/**
+ * 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.yarn.server.router.webapp.cache;
+
+import org.apache.commons.lang3.builder.EqualsBuilder;
+import org.apache.commons.lang3.builder.HashCodeBuilder;
+import org.apache.hadoop.security.UserGroupInformation;
+import org.apache.hadoop.yarn.server.resourcemanager.webapp.RMWebAppUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.servlet.http.HttpServletRequest;
+import java.util.Set;
+
+public class RouterAppInfoCacheKey {
+
+  private static String user = "YarnRouter";
+
+  private static final Logger LOG =
+      LoggerFactory.getLogger(RouterAppInfoCacheKey.class.getName());
+
+  private UserGroupInformation ugi;
+  private String stateQuery;
+  private Set<String> statesQuery;
+  private String finalStatusQuery;
+  private String userQuery;
+  private String queueQuery;
+  private String count;
+  private String startedBegin;
+  private String startedEnd;
+  private String finishBegin;
+  private String finishEnd;
+  private Set<String> applicationTypes;
+  private Set<String> applicationTags;
+  private String name;
+  private Set<String> unselectedFields;
+
+  public RouterAppInfoCacheKey() {
+
+  }
+
+  @SuppressWarnings("checkstyle:ParameterNumber")
+  public RouterAppInfoCacheKey(UserGroupInformation ugi, String stateQuery,
+      Set<String> statesQuery, String finalStatusQuery, String userQuery,
+      String queueQuery, String count, String startedBegin, String startedEnd,
+      String finishBegin, String finishEnd, Set<String> applicationTypes,
+      Set<String> applicationTags, String name, Set<String> unselectedFields) {
+    this.ugi = ugi;
+    this.stateQuery = stateQuery;
+    this.statesQuery = statesQuery;
+    this.finalStatusQuery = finalStatusQuery;
+    this.userQuery = userQuery;
+    this.queueQuery = queueQuery;
+    this.count = count;
+    this.startedBegin = startedBegin;
+    this.startedEnd = startedEnd;
+    this.finishBegin = finishBegin;
+    this.finishEnd = finishEnd;
+    this.applicationTypes = applicationTypes;
+    this.applicationTags = applicationTags;
+    this.name = name;
+    this.unselectedFields = unselectedFields;
+  }
+
+
+  @SuppressWarnings("checkstyle:ParameterNumber")
+  public static RouterAppInfoCacheKey newInstance(HttpServletRequest hsr, String stateQuery,
+      Set<String> statesQuery, String finalStatusQuery, String userQuery,
+      String queueQuery, String count, String startedBegin, String startedEnd,
+      String finishBegin, String finishEnd, Set<String> applicationTypes,
+      Set<String> applicationTags, String name, Set<String> unselectedFields)  {
+
+    UserGroupInformation callerUGI = null;
+    if (hsr != null) {
+      callerUGI = RMWebAppUtil.getCallerUserGroupInformation(hsr, true);
+    } else {
+      // user not required
+      callerUGI = UserGroupInformation.createRemoteUser("YarnRouter");
+    }
+
+    if (callerUGI == null) {
+      LOG.error("Unable to obtain user name, user not authenticated.");
+      return null;
+    }
+
+    return new RouterAppInfoCacheKey(
+        callerUGI, stateQuery, statesQuery, finalStatusQuery, userQuery,
+        queueQuery, count, startedBegin, startedEnd, finishBegin, finishEnd,
+        applicationTypes, applicationTags, name, unselectedFields);
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    RouterAppInfoCacheKey that = (RouterAppInfoCacheKey) o;
+
+    return new EqualsBuilder()
+        .append(this.ugi.getUserName(), that.ugi.getUserName())
+        .append(this.stateQuery, that.stateQuery)
+        .append(this.statesQuery, that.statesQuery)
+        .append(this.finalStatusQuery, that.finalStatusQuery)
+        .append(this.userQuery, that.userQuery)
+        .append(this.queueQuery, that.queueQuery)
+        .append(this.count, that.count)
+        .append(this.startedBegin, that.startedBegin)
+        .append(this.startedEnd, that.startedEnd)
+        .append(this.finishBegin, that.finishBegin)
+        .append(this.finishEnd, that.finishEnd)
+        .append(this.applicationTypes, that.applicationTypes)
+        .append(this.applicationTags, that.applicationTags)
+        .append(this.name, that.name)
+        .append(this.unselectedFields, that.unselectedFields)
+        .isEquals();
+  }
+
+  @Override
+  public int hashCode() {
+    return new HashCodeBuilder()
+       .append(this.ugi.getUserName())
+       .append(this.stateQuery)
+       .append(this.statesQuery)
+       .append(this.finalStatusQuery)
+       .append(this.userQuery)
+       .append(this.queueQuery)
+       .append(this.count)
+       .append(this.startedBegin)
+       .append(this.startedEnd)
+       .append(this.finishBegin)
+       .append(this.finishEnd)
+       .append(this.applicationTypes)
+       .append(this.applicationTags)
+       .append(this.name)
+       .append(this.unselectedFields)
+       .toHashCode();
+  }
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/webapp/cache/package-info.java

@@ -0,0 +1,18 @@
+/**
+ * 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.yarn.server.router.webapp.cache;

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/webapp/TestFederationInterceptorREST.java

@@ -72,10 +72,12 @@
 import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.AppPriority;
 import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.AppQueue;
 import org.apache.hadoop.yarn.server.resourcemanager.webapp.NodeIDsInfo;
+import org.apache.hadoop.yarn.server.router.webapp.cache.RouterAppInfoCacheKey;
 import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.ApplicationStatisticsInfo;
 import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.AppActivitiesInfo;
 import org.apache.hadoop.yarn.server.webapp.dao.ContainerInfo;
 import org.apache.hadoop.yarn.server.webapp.dao.ContainersInfo;
+import org.apache.hadoop.yarn.util.LRUCacheHashMap;
 import org.apache.hadoop.yarn.util.MonotonicClock;
 import org.apache.hadoop.yarn.util.Times;
 import org.junit.Assert;
@@ -160,6 +162,10 @@ protected YarnConfiguration createConfiguration() {
     // Disable StateStoreFacade cache
     conf.setInt(YarnConfiguration.FEDERATION_CACHE_TIME_TO_LIVE_SECS, 0);
 
+    // Open AppsInfo Cache
+    conf.setBoolean(YarnConfiguration.ROUTER_APPSINFO_ENABLED, true);
+    conf.setInt(YarnConfiguration.ROUTER_APPSINFO_CACHED_COUNT, 10);
+
     return conf;
   }
 
@@ -960,6 +966,28 @@ public void testGetAppQueue() throws IOException, InterruptedException, YarnExce
     Assert.assertEquals(queueName, queue.getQueue());
   }
 
+  @Test
+  public void testGetAppsInfoCache() throws IOException, InterruptedException, YarnException {
+
+    AppsInfo responseGet = interceptor.getApps(
+        null, null, null, null, null, null, null, null, null, null, null, null, null, null, null);
+    Assert.assertNotNull(responseGet);
+
+    RouterAppInfoCacheKey cacheKey = RouterAppInfoCacheKey.newInstance(
+        null, null, null, null, null, null, null, null, null, null, null, null, null, null, null);
+
+    LRUCacheHashMap<RouterAppInfoCacheKey, AppsInfo> appsInfoCache =
+        interceptor.getAppInfosCaches();
+    Assert.assertNotNull(appsInfoCache);
+    Assert.assertTrue(!appsInfoCache.isEmpty());
+    Assert.assertEquals(1, appsInfoCache.size());
+    Assert.assertTrue(appsInfoCache.containsKey(cacheKey));
+
+    AppsInfo cacheResult = appsInfoCache.get(cacheKey);
+    Assert.assertNotNull(cacheResult);
+    Assert.assertEquals(responseGet, cacheResult);
+  }
+
   @Test
   public void testGetAppStatistics() throws IOException, InterruptedException, YarnException {
     AppState appStateRUNNING = new AppState(YarnApplicationState.RUNNING.name());