HBASE-18645 Loads of tests timing out.... Revert "HBASE-14498 Master stuck in infinite loop when all Zookeeper servers are unreachable"

This reverts commit 1ab6882f62.

hbase-client/src/main/java/org/apache/hadoop/hbase/zookeeper/ZooKeeperWatcher.java

@@ -26,9 +26,6 @@ import java.util.List;
 import java.util.Map;
 import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -42,7 +39,6 @@ import org.apache.hadoop.hbase.HRegionInfo;
 import org.apache.hadoop.hbase.ZooKeeperConnectionException;
 import org.apache.hadoop.hbase.classification.InterfaceAudience;
 import org.apache.hadoop.hbase.security.Superusers;
-import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.zookeeper.KeeperException;
 import org.apache.zookeeper.WatchedEvent;
@@ -80,7 +76,7 @@ public class ZooKeeperWatcher implements Watcher, Abortable, Closeable {
   private final RecoverableZooKeeper recoverableZooKeeper;
 
   // abortable in case of zk failure
-  protected final Abortable abortable;
+  protected Abortable abortable;
   // Used if abortable is null
   private boolean aborted = false;
 
@@ -93,13 +89,6 @@ public class ZooKeeperWatcher implements Watcher, Abortable, Closeable {
   // negotiation to complete
   public CountDownLatch saslLatch = new CountDownLatch(1);
 
-  // Connection timeout on disconnect event
-  private long connWaitTimeOut;
-  private AtomicBoolean connected = new AtomicBoolean(false);
-  private boolean forceAbortOnZKDisconnect;
- 
-  // Execute service for zookeeper disconnect event watcher
-  private ExecutorService zkEventWatcherExecService = null;
 
 
   private final Configuration conf;
@@ -133,24 +122,6 @@ public class ZooKeeperWatcher implements Watcher, Abortable, Closeable {
   public ZooKeeperWatcher(Configuration conf, String identifier,
       Abortable abortable, boolean canCreateBaseZNode)
   throws IOException, ZooKeeperConnectionException {
-    this(conf, identifier, abortable, canCreateBaseZNode, false);
-  }
-
-  /**
-   * Instantiate a ZooKeeper connection and watcher.
-   * @param conf Configuration
-   * @param identifier string that is passed to RecoverableZookeeper to be used as identifier for
-   *          this instance. Use null for default.
-   * @param abortable Can be null if there is on error there is no host to abort: e.g. client
-   *          context.
-   * @param canCreateBaseZNode whether create base node.
-   * @param forceAbortOnZKDisconnect abort the watcher if true.
-   * @throws IOException when any IO exception
-   * @throws ZooKeeperConnectionException when any zookeeper connection exception
-   */
-  public ZooKeeperWatcher(Configuration conf, String identifier, Abortable abortable,
-      boolean canCreateBaseZNode, boolean forceAbortOnZKDisconnect) throws IOException,
-      ZooKeeperConnectionException {
     this.conf = conf;
     this.quorum = ZKConfig.getZKQuorumServersString(conf);
     this.prefix = identifier;
@@ -159,9 +130,6 @@ public class ZooKeeperWatcher implements Watcher, Abortable, Closeable {
     this.identifier = identifier + "0x0";
     this.abortable = abortable;
     this.znodePaths = new ZNodePaths(conf);
-    // On Disconnected event a thread will wait for sometime (2/3 of zookeeper.session.timeout),
-    // it will abort the process if no SyncConnected event reported by the time.
-    connWaitTimeOut = this.conf.getLong("zookeeper.session.timeout", 90000) * 2 / 3;
     PendingWatcher pendingWatcher = new PendingWatcher();
     this.recoverableZooKeeper = ZKUtil.connect(conf, quorum, pendingWatcher, identifier);
     pendingWatcher.prepare(this);
@@ -178,10 +146,6 @@ public class ZooKeeperWatcher implements Watcher, Abortable, Closeable {
         throw zce;
       }
     }
-    this.forceAbortOnZKDisconnect = forceAbortOnZKDisconnect;
-    if (this.forceAbortOnZKDisconnect) {
-      this.zkEventWatcherExecService = Executors.newSingleThreadExecutor();
-    }
   }
 
   private void createBaseZNodes() throws ZooKeeperConnectionException {
@@ -562,19 +526,11 @@ public class ZooKeeperWatcher implements Watcher, Abortable, Closeable {
           Long.toHexString(this.recoverableZooKeeper.getSessionId());
         // Update our identifier.  Otherwise ignore.
         LOG.debug(this.identifier + " connected");
-        connected.set(true);
         break;
 
       // Abort the server if Disconnected or Expired
       case Disconnected:
-        LOG.debug(prefix("Received Disconnected from ZooKeeper."));
-        if (forceAbortOnZKDisconnect) {
-          connected.set(false);
-          ZKDisconnectEventWatcher task = new ZKDisconnectEventWatcher();
-          zkEventWatcherExecService.execute(task);
-        } else {
-          LOG.debug("Received Disconnected from ZooKeeper, ignoring.");
-        }
+        LOG.debug(prefix("Received Disconnected from ZooKeeper, ignoring"));
         break;
 
       case Expired:
@@ -597,39 +553,6 @@ public class ZooKeeperWatcher implements Watcher, Abortable, Closeable {
     }
   }
 
-  /*
-   * Task to watch zookeper disconnect event.
-   */
-  class ZKDisconnectEventWatcher implements Runnable {
-    @Override
-    public void run() {
-      if (connected.get()) {
-        return;
-      }
-
-      long startTime = EnvironmentEdgeManager.currentTime();
-      while (EnvironmentEdgeManager.currentTime() - startTime < connWaitTimeOut) {
-        if (connected.get()) {
-          LOG.debug("Client got reconnected to zookeeper.");
-          return;
-        }
-        try {
-          Thread.sleep(100);
-        } catch (InterruptedException e) {
-          Thread.currentThread().interrupt();
-          break;
-        }
-      }
-
-      if (!connected.get() && abortable != null) {
-        String msg =
-            prefix("Couldn't connect to ZooKeeper after waiting " + connWaitTimeOut
-                + " ms, aborting");
-        abortable.abort(msg, new KeeperException.ConnectionLossException());
-      }
-    }
-  }
-
   /**
    * Forces a synchronization of this ZooKeeper client connection.
    * <p>
@@ -694,10 +617,6 @@ public class ZooKeeperWatcher implements Watcher, Abortable, Closeable {
   public void close() {
     try {
       recoverableZooKeeper.close();
-      if (zkEventWatcherExecService != null) {
-        zkEventWatcherExecService.shutdown();
-        zkEventWatcherExecService = null;
-      }
     } catch (InterruptedException e) {
       Thread.currentThread().interrupt();
     }

hbase-client/src/test/java/org/apache/hadoop/hbase/zookeeper/TestZooKeeperWatcher.java

@@ -23,22 +23,14 @@ import static org.junit.Assert.assertTrue;
 
 import java.io.IOException;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.ZooKeeperConnectionException;
 import org.apache.hadoop.hbase.testclassification.SmallTests;
-import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
-import org.apache.zookeeper.WatchedEvent;
-import org.apache.zookeeper.Watcher;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
 
 @Category({ SmallTests.class })
 public class TestZooKeeperWatcher {
-  private final static Log LOG = LogFactory.getLog(TestZooKeeperWatcher.class);
 
   @Test
   public void testIsClientReadable() throws ZooKeeperConnectionException, IOException {
@@ -65,43 +57,4 @@ public class TestZooKeeperWatcher {
     watcher.close();
   }
 
-  @Test
-  public void testConnectionEvent() throws ZooKeeperConnectionException, IOException {
-    long zkSessionTimeout = 15000l;
-    Configuration conf = HBaseConfiguration.create();
-    conf.set("zookeeper.session.timeout", "15000");
-
-    Abortable abortable = new Abortable() {
-      boolean aborted = false;
-
-      @Override
-      public void abort(String why, Throwable e) {
-        aborted = true;
-        LOG.error(why, e);
-      }
-
-      @Override
-      public boolean isAborted() {
-        return aborted;
-      }
-    };
-    ZooKeeperWatcher watcher = new ZooKeeperWatcher(conf, "testConnectionEvent", abortable, false, true);
-
-    WatchedEvent event =
-        new WatchedEvent(Watcher.Event.EventType.None, Watcher.Event.KeeperState.Disconnected, null);
-
-    long startTime = EnvironmentEdgeManager.currentTime();
-    while (!abortable.isAborted()
-        && (EnvironmentEdgeManager.currentTime() - startTime < zkSessionTimeout)) {
-      watcher.process(event);
-      try {
-        Thread.sleep(1000);
-      } catch (InterruptedException e) {
-        Thread.currentThread().interrupt();
-      }
-    }
-
-    assertTrue(abortable.isAborted());
-    watcher.close();
-  }
 }

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java

@@ -642,7 +642,7 @@ public class HRegionServer extends HasThread implements
     if (!conf.getBoolean("hbase.testing.nocluster", false)) {
       // Open connection to zookeeper and set primary watcher
       zooKeeper = new ZooKeeperWatcher(conf, getProcessName() + ":" +
-        rpcServices.isa.getPort(), this, canCreateBaseZNode(), true);
+        rpcServices.isa.getPort(), this, canCreateBaseZNode());
 
       this.csm = (BaseCoordinatedStateManager) csm;
       this.csm.initialize(this);