Github user karanmehta93 commented on a diff in the pull request:
https://github.com/apache/phoenix/pull/359#discussion_r222440911
--- Diff:
phoenix-core/src/main/java/org/apache/phoenix/coprocessor/TaskRegionObserver.java
---
@@ -0,0 +1,261 @@
+/*
+ * 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.phoenix.coprocessor;
+
+import java.io.IOException;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Timestamp;
+import java.sql.Types;
+
+import java.util.Optional;
+import java.util.Properties;
+import java.util.TimerTask;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+
+import javax.annotation.concurrent.GuardedBy;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.CoprocessorEnvironment;
+import org.apache.hadoop.hbase.coprocessor.ObserverContext;
+import org.apache.hadoop.hbase.coprocessor.RegionCoprocessor;
+import org.apache.hadoop.hbase.coprocessor.RegionCoprocessorEnvironment;
+import org.apache.hadoop.hbase.coprocessor.RegionObserver;
+import org.apache.log4j.Level;
+import org.apache.log4j.Logger;
+import org.apache.phoenix.jdbc.PhoenixConnection;
+import org.apache.phoenix.jdbc.PhoenixDatabaseMetaData;
+import org.apache.phoenix.jdbc.PhoenixDriver;
+import org.apache.phoenix.query.QueryServices;
+import org.apache.phoenix.query.QueryServicesOptions;
+import org.apache.phoenix.schema.MetaDataClient;
+import org.apache.phoenix.schema.PTable;
+import org.apache.phoenix.schema.PTable.TaskType;
+
+import org.apache.phoenix.util.PhoenixRuntime;
+import org.apache.phoenix.util.QueryUtil;
+
+
+/**
+ * Coprocessor for task related operations. This coprocessor would only be
registered
+ * to SYSTEM.TASK table
+ */
+@SuppressWarnings("deprecation")
+public class TaskRegionObserver implements RegionObserver,
RegionCoprocessor {
+ public static final Log LOG =
LogFactory.getLog(TaskRegionObserver.class);
+ protected ScheduledThreadPoolExecutor executor = new
ScheduledThreadPoolExecutor(TaskType.values().length);
--- End diff --
I think that its better to make the number of threads configurable and not
based on `TaskType` only. We don't often drop tables, but if the variety and
heterogeneity of tasks grow in future, we definitely should be able to get
more. IMHO, 4 threads should be good default to start with.
---
