YARN-11286. Make AsyncDispatcher#printEventDetailsExecutor thread pool parameter configurable. (#4824). Contributed by fanshilun.

Signed-off-by: Ayush Saxena <ayushsaxena@apache.org>

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

@@ -2987,6 +2987,51 @@ public class YarnConfiguration extends Configuration {
   public static final int
       DEFAULT_YARN_DISPATCHER_CPU_MONITOR_SAMPLES_PER_MIN = 60;
 
+  /**
+   * Resource manager dispatcher has a thread pool that prints EventQueue,
+   * configure the corePoolSize of this thread pool,
+   * the meaning of corePoolSize is the number of threads to keep in the pool.
+   */
+  public static final String YARN_DISPATCHER_PRINT_THREAD_POOL_CORE_POOL_SIZE =
+      YARN_PREFIX + "dispatcher.print-thread-pool.core-pool-size";
+
+  /**
+   * The minimum number of core threads for the
+   * Resource manager dispatcher is 1.
+   */
+  public static final int DEFAULT_YARN_DISPATCHER_PRINT_THREAD_POOL_CORE_POOL_SIZE = 1;
+
+  /**
+   * Resource manager dispatcher has a thread pool that prints EventQueue,
+   * configure the maximumPoolSize of this thread pool,
+   * the meaning of maximumPoolSize is the maximum number of threads to allow in the pool.
+   */
+  public static final String YARN_DISPATCHER_PRINT_THREAD_POOL_MAXIMUM_POOL_SIZE =
+      YARN_PREFIX + "dispatcher.print-thread-pool.maximum-pool-size";
+
+  /**
+   * The maximum number of core threads for the
+   * Resource manager dispatcher is 5.
+   */
+  public static final int DEFAULT_YARN_DISPATCHER_PRINT_THREAD_POOL_MAXIMUM_POOL_SIZE = 5;
+
+  /**
+   * Resource manager dispatcher has a thread pool that prints EventQueue,
+   * configure the keepAliveTime of this thread pool,
+   * The meaning of keepAliveTime is as follows
+   * when the number of threads is greater than the core,
+   * this is the maximum time that excess idle threads will wait for new tasks before terminating.
+   */
+  public static final String YARN_DISPATCHER_PRINT_THREAD_POOL_KEEP_ALIVE_TIME =
+      YARN_PREFIX + "dispatcher.print-thread-pool.keep-alive-time";
+
+  /**
+   * The keep alive time of core threads for the
+   * Resource manager dispatcher is 10s.
+   */
+  public static final long DEFAULT_YARN_DISPATCHER_PRINT_THREAD_POOL_KEEP_ALIVE_TIME =
+      10*1000; // 10s
+
   /**
    * CLASSPATH for YARN applications. A comma-separated list of CLASSPATH
    * entries

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/event/AsyncDispatcher.java

@@ -191,8 +191,21 @@ public class AsyncDispatcher extends AbstractService implements Dispatcher {
         .build();
     // Thread pool for async print event details,
     // to prevent wasting too much time for RM.
+    int numCorePoolSizeThreads = getConfig().getInt(
+        YarnConfiguration.YARN_DISPATCHER_PRINT_THREAD_POOL_CORE_POOL_SIZE,
+        YarnConfiguration.DEFAULT_YARN_DISPATCHER_PRINT_THREAD_POOL_CORE_POOL_SIZE);
+
+    int numMaximumPoolSizeThreads = getConfig().getInt(
+        YarnConfiguration.YARN_DISPATCHER_PRINT_THREAD_POOL_MAXIMUM_POOL_SIZE,
+        YarnConfiguration.DEFAULT_YARN_DISPATCHER_PRINT_THREAD_POOL_MAXIMUM_POOL_SIZE);
+
+    long keepAliveTime =
+         conf.getTimeDuration(YarnConfiguration.YARN_DISPATCHER_PRINT_THREAD_POOL_KEEP_ALIVE_TIME,
+         YarnConfiguration.DEFAULT_YARN_DISPATCHER_PRINT_THREAD_POOL_KEEP_ALIVE_TIME,
+         TimeUnit.SECONDS);
+
     printEventDetailsExecutor = new ThreadPoolExecutor(
-        1, 5, 10, TimeUnit.SECONDS,
+        numCorePoolSizeThreads, numMaximumPoolSizeThreads, keepAliveTime, TimeUnit.SECONDS,
         new LinkedBlockingQueue<>(), threadFactory);
   }
 

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

@@ -133,6 +133,41 @@
     <value>60</value>
   </property>
 
+  <property>
+    <description>
+      Resource manager dispatcher has a thread pool that prints EventQueue,
+      configure the corePoolSize of this thread pool,
+      the meaning of corePoolSize is the number of threads to keep in the pool.
+      the default value is 1.
+    </description>
+    <name>yarn.dispatcher.print-thread-pool.core-pool-size</name>
+    <value>1</value>
+  </property>
+
+  <property>
+    <description>
+      Resource manager dispatcher has a thread pool that prints EventQueue,
+      configure the maximumPoolSize of this thread pool,
+      the meaning of maximumPoolSize is the maximum number of threads to allow in the pool.
+      the default value is 5.
+    </description>
+    <name>yarn.dispatcher.print-thread-pool.maximum-pool-size</name>
+    <value>5</value>
+  </property>
+
+  <property>
+    <description>
+      Resource manager dispatcher has a thread pool that prints EventQueue,
+      configure the keepAliveTime of this thread pool,
+      The meaning of keepAliveTime is as follows
+      when the number of threads is greater than the core,
+      this is the maximum time that excess idle threads will wait for new tasks before terminating.
+      the default value is 10s.
+    </description>
+    <name>yarn.dispatcher.print-thread-pool.keep-alive-time</name>
+    <value>10s</value>
+  </property>
+
   <property>
     <description>The expiry interval for application master reporting.</description>
     <name>yarn.am.liveness-monitor.expiry-interval-ms</name>