mcvsubbu commented on a change in pull request #4993: Support Text column type 
in Pinot (both offline and realtime)
URL: https://github.com/apache/incubator-pinot/pull/4993#discussion_r379148300
 
 

 ##########
 File path: 
pinot-core/src/main/java/org/apache/pinot/core/realtime/impl/invertedindex/RealtimeLuceneIndexReaderRefreshThread.java
 ##########
 @@ -0,0 +1,133 @@
+/**
+ * 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.pinot.core.realtime.impl.invertedindex;
+
+import java.util.List;
+import java.util.concurrent.ConcurrentLinkedQueue;
+import java.util.concurrent.locks.Condition;
+import java.util.concurrent.locks.Lock;
+import org.apache.lucene.search.SearcherManager;
+import org.apache.lucene.store.AlreadyClosedException;
+import org.apache.pinot.core.segment.creator.impl.SegmentColumnarIndexCreator;
+import 
org.apache.pinot.core.realtime.impl.invertedindex.RealtimeLuceneIndexRefreshState.RealtimeLuceneReadersForRealtimeSegment;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+
+/**
+ * Background thread to refresh the realtime lucene index readers for 
supporting
+ * near-realtime text search. The task maintains a queue of realtime segments.
+ * This queue is global (across all realtime segments of all realtime/hybrid 
tables).
+ *
+ * Each element in the queue is of type {@link 
RealtimeLuceneReadersForRealtimeSegment}.
+ * It encapsulates a lock and all the realtime lucene readers for the 
particular realtime segment.
+ * Since text index is also create on a per column basis, there will be as 
many realtime lucene
+ * readers as the number of columns with text search enabled.
+ *
+ * Between each successive execution of the task, there is a fixed delay 
(regardless of how long
+ * each execution took). When the task wakes up, it pick the 
RealtimeLuceneReadersForRealtimeSegment
+ * from the head of queue, refresh it's readers and adds this at the tail of 
queue.
+ */
+public class RealtimeLuceneIndexReaderRefreshThread implements Runnable {
+  private static final Logger LOGGER = 
LoggerFactory.getLogger(SegmentColumnarIndexCreator.class);
+  // TODO: make this configurable and choose a higher default value
+  public static final int DELAY_BETWEEN_SUCCESSIVE_EXECUTION_MS_DEFAULT = 10;
+
+  private final ConcurrentLinkedQueue<RealtimeLuceneReadersForRealtimeSegment> 
_luceneRealtimeReaders;
+  private final Lock _mutex;
+  private final Condition _conditionVariable;
+
+  private volatile boolean _stopped = false;
+
+  RealtimeLuceneIndexReaderRefreshThread(
+      ConcurrentLinkedQueue<RealtimeLuceneReadersForRealtimeSegment> 
luceneRealtimeReaders,
+      Lock mutex, Condition conditionVariable) {
+    _luceneRealtimeReaders = luceneRealtimeReaders;
+    _mutex = mutex;
+    _conditionVariable = conditionVariable;
+  }
+
+  void setStopped() {
+    _stopped = true;
+  }
+
+  @Override
+  public void run() {
+    while (_stopped) {
+      _mutex.lock();
+      while (_luceneRealtimeReaders.isEmpty()) {
+        try {
+          // During instantiation of MutableSegmentImpl, we will signal on 
this condition variable once
 
 Review comment:
   as many times as there are mutable segments

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscr...@pinot.apache.org
For additional commands, e-mail: commits-h...@pinot.apache.org

Reply via email to