[GitHub] [hbase] virajjasani commented on a change in pull request #2052: HBASE-24718 : Generic NamedQueue framework for multiple use-cases (Refactor SlowLog responses)

[GitBox <gi...@apache.org>]

virajjasani commented on a change in pull request #2052:
URL: https://github.com/apache/hbase/pull/2052#discussion_r453588358



##########
File path: hbase-server/src/main/java/org/apache/hadoop/hbase/namequeues/SlowLogPersistentService.java
##########
@@ -0,0 +1,98 @@
+/*
+ *
+ * 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.hadoop.hbase.namequeues;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.shaded.protobuf.generated.TooSlowLog;
+import org.apache.hadoop.hbase.slowlog.SlowLogTableAccessor;
+import org.apache.hbase.thirdparty.com.google.common.collect.EvictingQueue;
+import org.apache.hbase.thirdparty.com.google.common.collect.Queues;
+import org.apache.yetus.audience.InterfaceAudience;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Queue;
+import java.util.concurrent.locks.ReentrantLock;
+
+/**
+ * Persistent service provider for Slow/LargeLog events
+ */
+@InterfaceAudience.Private
+public class SlowLogPersistentService {

Review comment:
       This is persistence service. Not all use-cases are supposed to have persistence, and even if they have, implementation might differ: Some use-case might prefer using Zookeeper (just a thought), others might want independent system table or shared system table. 
   
   Hence, persistence service can be specific to corresponding use-cases. Let me see if interface will be of use here. Interface with strategy pattern can be real beneficial for in-memory layer since that is the primary use-case, let me think about persistence since it is not always going to be used by all use-cases.

##########
File path: hbase-server/src/main/java/org/apache/hadoop/hbase/namequeues/LogEventHandler.java
##########
@@ -50,64 +50,83 @@
 import org.apache.hadoop.hbase.shaded.protobuf.generated.TooSlowLog.SlowLogPayload;
 
 /**
- * Event Handler run by disruptor ringbuffer consumer
+ * Event Handler run by disruptor ringbuffer consumer.
+ * Although this is generic implementation for namedQueue, it can have individual queue specific
+ * logic.
  */
 @InterfaceAudience.Private
 class LogEventHandler implements EventHandler<RingBufferEnvelope> {
 
   private static final Logger LOG = LoggerFactory.getLogger(LogEventHandler.class);
 
-  private static final String SYS_TABLE_QUEUE_SIZE =
-    "hbase.regionserver.slowlog.systable.queue.size";
-  private static final int DEFAULT_SYS_TABLE_QUEUE_SIZE = 1000;
-  private static final int SYSTABLE_PUT_BATCH_SIZE = 100;
+  private static final String SLOW_LOG_RING_BUFFER_SIZE =
+    "hbase.regionserver.slowlog.ringbuffer.size";
+
+  // Map that binds namedQueues.
+  // If NamedQueue of specific type is enabled, corresponding Queue will be used to
+  // insert and retrieve records.
+  // Individual queue sizes should be determined based on their individual configs.
+  private final Map<NamedQueuePayload.NamedQueueEvent, Queue> namedQueues = new HashMap<>();

Review comment:
       Strategy pattern is good thought but we don't have common payload coming from client so far. Specifically when admin client will talk to RSRpcServer and that will talk to `LogEventHandler`, they expect specific payload for specific use-case. However, this fits well for strategy pattern and we should have common request payload. Let me try this one. Thanks for the suggestion @wchevreuil .




----------------------------------------------------------------
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:
users@infra.apache.org