| /* |
| * 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.chukwa.datacollection.agent; |
| |
| |
| import java.util.LinkedList; |
| import java.util.List; |
| import java.util.Queue; |
| import org.apache.hadoop.chukwa.Chunk; |
| import org.apache.hadoop.chukwa.datacollection.ChunkQueue; |
| import org.apache.hadoop.chukwa.datacollection.agent.metrics.ChunkQueueMetrics; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.log4j.Logger; |
| |
| /** |
| * An event queue that blocks once a fixed upper limit of data is enqueued. |
| * |
| * For now, uses the size of the data field. Should really use |
| * estimatedSerializedSize()? |
| * |
| */ |
| public class MemLimitQueue implements ChunkQueue { |
| static Logger log = Logger.getLogger(WaitingQueue.class); |
| static final ChunkQueueMetrics metrics = new ChunkQueueMetrics("chukwaAgent", "chunkQueue");; |
| private Queue<Chunk> queue = new LinkedList<Chunk>(); |
| private long dataSize = 0; |
| private long MAX_MEM_USAGE; |
| static final String CHUNK_QUEUE_LIMIT = "chukwaAgent.chunk.queue.limit"; |
| static final int QUEUE_SIZE = 10 * 1024 * 1024; |
| |
| public MemLimitQueue(Configuration conf) { |
| configure(conf); |
| } |
| |
| /** |
| * @see org.apache.hadoop.chukwa.datacollection.ChunkQueue#add(org.apache.hadoop.chukwa.Chunk) |
| */ |
| public void add(Chunk chunk) throws InterruptedException { |
| assert chunk != null : "can't enqueue null chunks"; |
| synchronized (this) { |
| while (chunk.getData().length + dataSize > MAX_MEM_USAGE) { |
| try { |
| if(dataSize == 0) { //queue is empty, but data is still too big |
| log.error("JUMBO CHUNK SPOTTED: type= " + chunk.getDataType() + |
| " and source =" +chunk.getStreamName()); |
| return; //return without sending; otherwise we'd deadlock. |
| //this error should probably be fatal; there's no way to recover. |
| } |
| metrics.fullQueue.set(1); |
| this.wait(); |
| log.info("MemLimitQueue is full [" + dataSize + "]"); |
| } catch (InterruptedException e) { |
| } |
| } |
| metrics.fullQueue.set(0); |
| dataSize += chunk.getData().length; |
| queue.add(chunk); |
| metrics.addedChunk.inc(); |
| metrics.queueSize.set(queue.size()); |
| metrics.dataSize.set(dataSize); |
| this.notifyAll(); |
| } |
| |
| } |
| |
| /** |
| * @see org.apache.hadoop.chukwa.datacollection.ChunkQueue#collect(java.util.List, |
| * int) |
| */ |
| public void collect(List<Chunk> events, int maxSize) |
| throws InterruptedException { |
| synchronized (this) { |
| // we can't just say queue.take() here, since we're holding a lock. |
| while (queue.isEmpty()) { |
| this.wait(); |
| } |
| |
| int size = 0; |
| while (!queue.isEmpty() && (size < maxSize)) { |
| Chunk e = this.queue.remove(); |
| metrics.removedChunk.inc(); |
| int chunkSize = e.getData().length; |
| size += chunkSize; |
| dataSize -= chunkSize; |
| metrics.dataSize.set(dataSize); |
| events.add(e); |
| } |
| metrics.queueSize.set(queue.size()); |
| this.notifyAll(); |
| } |
| |
| if (log.isDebugEnabled()) { |
| log.debug("WaitingQueue.inQueueCount:" + queue.size() |
| + "\tWaitingQueue.collectCount:" + events.size()); |
| } |
| } |
| |
| public int size() { |
| return queue.size(); |
| } |
| |
| private void configure(Configuration conf) { |
| MAX_MEM_USAGE = QUEUE_SIZE; |
| if(conf == null){ |
| return; |
| } |
| String limit = conf.get(CHUNK_QUEUE_LIMIT); |
| if(limit != null){ |
| try{ |
| MAX_MEM_USAGE = Integer.parseInt(limit); |
| } catch(NumberFormatException nfe) { |
| log.error("Exception reading property " + CHUNK_QUEUE_LIMIT |
| + ". Defaulting internal queue size to " + QUEUE_SIZE); |
| } |
| } |
| log.info("Using MemLimitQueue limit of " + MAX_MEM_USAGE); |
| } |
| } |