Optimize heartbeat (#3299)

* Optimize heartbeat.
We should cancel the timeout when the client or server is close.

* change the hashedWheelTimer's ticks

* Optimize tasks keeper.

* fix timeout cancel to task cancel.
keep task directly.

Author: carryxyh

dubbo-common/src/main/java/org/apache/dubbo/common/Constants.java

@@ -300,9 +300,9 @@ public class Constants {
     public static final long LEAST_HEARTBEAT_DURATION = 1000;
 
     /**
-     * ticks per wheel. Currently only contains two tasks, so 16 locations are enough
+     * ticks per wheel.
      */
-    public static final int TICKS_PER_WHEEL = 16;
+    public static final int TICKS_PER_WHEEL = 128;
 
     public static final String HEARTBEAT_TIMEOUT_KEY = "heartbeat.timeout";
 

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/exchange/support/header/AbstractTimerTask.java

@@ -34,6 +34,8 @@ public abstract class AbstractTimerTask implements TimerTask {
 
     private final Long tick;
 
+    protected volatile boolean cancel = false;
+
     AbstractTimerTask(ChannelProvider channelProvider, Long tick) {
         if (channelProvider == null || tick == null) {
             throw new IllegalArgumentException();
@@ -54,11 +56,19 @@ static Long now() {
         return System.currentTimeMillis();
     }
 
+    public void cancel() {
+        this.cancel = true;
+    }
+
     private void reput(Timeout timeout, Long tick) {
         if (timeout == null || tick == null) {
             throw new IllegalArgumentException();
         }
 
+        if (cancel) {
+            return;
+        }
+
         Timer timer = timeout.timer();
         if (timer.isStop() || timeout.isCancelled()) {
             return;

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/exchange/support/header/HeaderExchangeClient.java

@@ -43,9 +43,13 @@ public class HeaderExchangeClient implements ExchangeClient {
     private int heartbeat;
     private int idleTimeout;
 
-    private static HashedWheelTimer idleCheckTimer = new HashedWheelTimer(new NamedThreadFactory("dubbo-client-idleCheck", true), 1,
+    private static final HashedWheelTimer IDLE_CHECK_TIMER = new HashedWheelTimer(new NamedThreadFactory("dubbo-client-idleCheck", true), 1,
             TimeUnit.SECONDS, Constants.TICKS_PER_WHEEL);
 
+    private HeartbeatTimerTask heartBeatTimerTask;
+
+    private ReconnectTimerTask reconnectTimerTask;
+
     public HeaderExchangeClient(Client client, boolean needHeartbeat) {
         Assert.notNull(client, "Client can't be null");
         this.client = client;
@@ -182,12 +186,17 @@ private void startIdleCheckTask() {
         HeartbeatTimerTask heartBeatTimerTask = new HeartbeatTimerTask(cp, heartbeatTick, heartbeat);
         ReconnectTimerTask reconnectTimerTask = new ReconnectTimerTask(cp, heartbeatTimeoutTick, idleTimeout);
 
+        this.heartBeatTimerTask = heartBeatTimerTask;
+        this.reconnectTimerTask = reconnectTimerTask;
+
         // init task and start timer.
-        idleCheckTimer.newTimeout(heartBeatTimerTask, heartbeatTick, TimeUnit.MILLISECONDS);
-        idleCheckTimer.newTimeout(reconnectTimerTask, heartbeatTimeoutTick, TimeUnit.MILLISECONDS);
+        IDLE_CHECK_TIMER.newTimeout(heartBeatTimerTask, heartbeatTick, TimeUnit.MILLISECONDS);
+        IDLE_CHECK_TIMER.newTimeout(reconnectTimerTask, heartbeatTimeoutTick, TimeUnit.MILLISECONDS);
     }
 
     private void doClose() {
+        heartBeatTimerTask.cancel();
+        reconnectTimerTask.cancel();
     }
 
     /**

dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/exchange/support/header/HeaderExchangeServer.java

@@ -53,9 +53,11 @@ public class HeaderExchangeServer implements ExchangeServer {
     private int idleTimeout;
     private AtomicBoolean closed = new AtomicBoolean(false);
 
-    private static HashedWheelTimer idleCheckTimer = new HashedWheelTimer(new NamedThreadFactory("dubbo-server-idleCheck", true), 1,
+    private static final HashedWheelTimer IDLE_CHECK_TIMER = new HashedWheelTimer(new NamedThreadFactory("dubbo-server-idleCheck", true), 1,
             TimeUnit.SECONDS, Constants.TICKS_PER_WHEEL);
 
+    private CloseTimerTask closeTimerTask;
+
     public HeaderExchangeServer(Server server) {
         Assert.notNull(server, "server == null");
         this.server = server;
@@ -148,6 +150,11 @@ private void doClose() {
         if (!closed.compareAndSet(false, true)) {
             return;
         }
+        cancelCloseTask();
+    }
+
+    private void cancelCloseTask() {
+        closeTimerTask.cancel();
     }
 
     @Override
@@ -214,6 +221,8 @@ public void reset(URL url) {
                     heartbeat = h;
                     idleTimeout = t;
 
+                    // we need cancel the exist closeTimeout first.
+                    cancelCloseTask();
                     startIdleCheckTask();
                 }
             }
@@ -262,9 +271,10 @@ private void startIdleCheckTask() {
 
         long idleTimeoutTick = calculateLeastDuration(idleTimeout);
         CloseTimerTask closeTimerTask = new CloseTimerTask(cp, idleTimeoutTick, idleTimeout);
+        this.closeTimerTask = closeTimerTask;
 
         // init task and start timer.
-        idleCheckTimer.newTimeout(closeTimerTask, idleTimeoutTick, TimeUnit.MILLISECONDS);
+        IDLE_CHECK_TIMER.newTimeout(closeTimerTask, idleTimeoutTick, TimeUnit.MILLISECONDS);
     }
 
 }