Backout fix for SOLR-6631 as things like create collection are hanging now

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1635155 13f79535-47bb-0310-9956-ffa450edef68

solr/CHANGES.txt

@@ -278,9 +278,6 @@ Bug Fixes
 * SOLR-6591: Overseer can use stale cluster state and lose updates for collections
   with stateFormat > 1. (shalin)
 
-* SOLR-6631: DistributedQueue spinning on calling zookeeper getChildren()
-  (Jessica Cheng Mallet, Mark Miller, Timothy Potter)
-
 Optimizations
 ----------------------
 

solr/core/src/java/org/apache/solr/cloud/DistributedQueue.java

@@ -246,14 +246,11 @@ public class DistributedQueue {
     
     @Override
     public void process(WatchedEvent event) {
-      Event.EventType eventType = event.getType();
       LOG.info("LatchChildWatcher fired on path: " + event.getPath() + " state: "
-          + event.getState() + " type " + eventType);
+          + event.getState() + " type " + event.getType());
-      if (eventType == Event.EventType.NodeChildrenChanged) {
+      synchronized (lock) {
-        synchronized (lock) {
+        this.event = event;
-          this.event = event;
+        lock.notifyAll();
-          lock.notifyAll();
-        }
       }
     }
     

solr/core/src/test/org/apache/solr/cloud/DistributedQueueTest.java

@@ -1,131 +0,0 @@
-package org.apache.solr.cloud;
-/*
- * 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.
- */
-
-import java.io.File;
-
-import org.apache.solr.SolrTestCaseJ4;
-import org.apache.solr.common.cloud.SolrZkClient;
-import org.apache.solr.cloud.DistributedQueue.QueueEvent;
-
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-
-public class DistributedQueueTest extends SolrTestCaseJ4 {
-
-  protected ZkTestServer zkServer;
-  protected SolrZkClient zkClient;
-
-  @Before
-  @Override
-  public void setUp() throws Exception {
-    super.setUp();
-    setupZk();
-  }
-
-  @Test
-  public void testDistributedQueue() throws Exception {
-    String dqZNode = "/distqueue/test";
-    String testData = "hello world";
-    long timeoutMs = 500L;
-
-    DistributedQueue dq = new DistributedQueue(zkClient, setupDistributedQueueZNode(dqZNode));
-
-    // basic ops
-    assertTrue(dq.poll() == null);
-    byte[] data = testData.getBytes("UTF-8");
-    dq.offer(data);
-    assertEquals(new String(dq.peek(),"UTF-8"), testData);
-    assertEquals(new String(dq.take(),"UTF-8"), testData);
-    assertTrue(dq.poll() == null);
-    QueueEvent qe = dq.offer(data, timeoutMs);
-    assertNotNull(qe);
-    assertEquals(new String(dq.remove(),"UTF-8"), testData);
-
-    // should block until the background thread makes the offer
-    (new QueueChangerThread(dq, 1000)).start();
-    qe = dq.peek(true);
-    assertNotNull(qe);
-    dq.remove();
-
-    // timeout scenario ... background thread won't offer until long after the peek times out
-    QueueChangerThread qct = new QueueChangerThread(dq, 1000);
-    qct.start();
-    qe = dq.peek(500);
-    assertTrue(qe == null);
-
-    try {
-      qct.interrupt();
-    } catch (Exception exc) {}
-  }
-
-  private class QueueChangerThread extends Thread {
-
-    DistributedQueue dq;
-    long waitBeforeOfferMs;
-
-    QueueChangerThread(DistributedQueue dq, long waitBeforeOfferMs) {
-      this.dq = dq;
-      this.waitBeforeOfferMs = waitBeforeOfferMs;
-    }
-
-    public void run() {
-      try {
-        Thread.sleep(waitBeforeOfferMs);
-        dq.offer(getName().getBytes("UTF-8"));
-      } catch (InterruptedException ie) {
-        // do nothing
-      } catch (Exception exc) {
-        throw new RuntimeException(exc);
-      }
-    }
-  }
-
-  protected String setupDistributedQueueZNode(String znodePath) throws Exception {
-    if (!zkClient.exists("/", true))
-      zkClient.makePath("/", false, true);
-    if (zkClient.exists(znodePath, true))
-      zkClient.clean(znodePath);
-    zkClient.makePath(znodePath, false, true);
-    return znodePath;
-  }
-
-  @Override
-  @After
-  public void tearDown() throws Exception {
-    try {
-      super.tearDown();
-    } catch (Exception exc) {}
-    closeZk();
-  }
-
-  protected void setupZk() throws Exception {
-    System.setProperty("zkClientTimeout", "8000");
-    zkServer = new ZkTestServer(createTempDir("zkData").toFile().getAbsolutePath());
-    zkServer.run();
-    System.setProperty("zkHost", zkServer.getZkAddress());
-    zkClient = new SolrZkClient(zkServer.getZkAddress(), AbstractZkTestCase.TIMEOUT);
-    assertTrue(zkClient.isConnected());
-  }
-
-  protected void closeZk() throws Exception {
-    if (zkClient != null)
-      zkClient.close();
-    zkServer.shutdown();
-  }
-}