Size queue based on thread pool size

Author: ndimiduk

hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/replication/VerifyReplication.java

@@ -135,7 +135,7 @@ public class VerifyReplication extends Configured implements Tool {
   public static class Verifier extends TableMapper<ImmutableBytesWritable, Put> {
 
     private ThreadPoolExecutor reCompareExecutor = null;
-    private final LinkedBlockingQueue<Future<?>> reCompareTasks = new LinkedBlockingQueue<>(1_000);
+    private LinkedBlockingQueue<Future<?>> reCompareTasks = null;
 
     public enum Counters {
       GOODROWS,
@@ -202,6 +202,7 @@ private ResultScanner initializeMapperOnFirstValue(Context context, Result value
       }
       int reCompareThreads = conf.getInt(NAME + ".recompareThreads", 0);
       reCompareExecutor = buildReCompareExecutor(reCompareThreads, context);
+      reCompareTasks = buildReCompareTasksQueue(reCompareThreads);
       TableName tableName = TableName.valueOf(conf.get(NAME + ".tableName"));
       sourceConnection = ConnectionFactory.createConnection(conf);
       sourceTable = sourceConnection.getTable(tableName);
@@ -330,6 +331,15 @@ private Future<?> logFailRowAndIncreaseCounter(Context context, Counters counter
 
     private void addSubmittedTaskToQueue(Future<?> task, Context context, Result value,
       String method) {
+      if (reCompareTasks == null) {
+        try {
+          task.get();
+        } catch (Exception e) {
+          throw new RuntimeException(e);
+        }
+        return;
+      }
+
       while (true) {
         if (reCompareTasks.offer(task)) {
           break;
@@ -459,6 +469,10 @@ public void rejectedExecution(Runnable runnable, ThreadPoolExecutor e) {
         }
       };
     }
+
+    private static LinkedBlockingQueue<Future<?>> buildReCompareTasksQueue(int maxThreads) {
+      return maxThreads <= 0 ? null : new LinkedBlockingQueue<>(maxThreads * 10);
+    }
   }
 
   private static Pair<ReplicationPeerConfig, Configuration>