| /* |
| * 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.iotdb.db.storageengine.dataregion.wal.allocation; |
| |
| import org.apache.iotdb.commons.utils.FileUtils; |
| import org.apache.iotdb.consensus.iot.log.ConsensusReqReader; |
| import org.apache.iotdb.db.storageengine.dataregion.wal.WALManager; |
| import org.apache.iotdb.db.storageengine.dataregion.wal.node.IWALNode; |
| import org.apache.iotdb.db.storageengine.dataregion.wal.node.WALNode; |
| |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.concurrent.locks.Lock; |
| import java.util.concurrent.locks.ReentrantLock; |
| |
| /** |
| * This strategy creates one wal node for each unique identifier. In other words, each identifier |
| * (like data region) has its own wal node. |
| */ |
| public class FirstCreateStrategy extends AbstractNodeAllocationStrategy { |
| // protect concurrent safety of wal nodes, including walNodes, nodeCursor and nodeIdCounter |
| private final Lock nodesLock = new ReentrantLock(); |
| // region these variables should be protected by nodesLock |
| // wal nodes |
| private final Map<String, WALNode> identifier2Nodes = new HashMap<>(); |
| |
| // endregion |
| |
| // it's safe to not close WALNode here, we use clear method to close all WALNodes. |
| @SuppressWarnings("squid:S2095") |
| @Override |
| public IWALNode applyForWALNode(String applicantUniqueId) { |
| nodesLock.lock(); |
| try { |
| if (!identifier2Nodes.containsKey(applicantUniqueId)) { |
| IWALNode walNode = createWALNode(applicantUniqueId); |
| if (walNode instanceof WALNode) { |
| // avoid deletion |
| walNode.setSafelyDeletedSearchIndex( |
| ConsensusReqReader.DEFAULT_SAFELY_DELETED_SEARCH_INDEX); |
| identifier2Nodes.put(applicantUniqueId, (WALNode) walNode); |
| } |
| } |
| |
| return identifier2Nodes.get(applicantUniqueId); |
| } finally { |
| nodesLock.unlock(); |
| } |
| } |
| |
| public void registerWALNode( |
| String applicantUniqueId, String logDirectory, long startFileVersion, long startSearchIndex) { |
| nodesLock.lock(); |
| try { |
| if (identifier2Nodes.containsKey(applicantUniqueId)) { |
| return; |
| } |
| // Although walNode is defined as a local variable, it is added into a global var |
| // identifier2Nodes later. So we cannot close it here. |
| @SuppressWarnings("squid:S2095") |
| IWALNode walNode = |
| createWALNode(applicantUniqueId, logDirectory, startFileVersion, startSearchIndex); |
| if (walNode instanceof WALNode) { |
| // avoid deletion |
| walNode.setSafelyDeletedSearchIndex(ConsensusReqReader.DEFAULT_SAFELY_DELETED_SEARCH_INDEX); |
| identifier2Nodes.put(applicantUniqueId, (WALNode) walNode); |
| } |
| } finally { |
| nodesLock.unlock(); |
| } |
| } |
| |
| public void deleteWALNode(String applicantUniqueId) { |
| nodesLock.lock(); |
| try { |
| WALNode walNode = identifier2Nodes.remove(applicantUniqueId); |
| if (walNode != null) { |
| walNode.close(); |
| if (walNode.getLogDirectory().exists()) { |
| FileUtils.deleteFileOrDirectory(walNode.getLogDirectory()); |
| } |
| WALManager.getInstance().subtractTotalDiskUsage(walNode.getDiskUsage()); |
| WALManager.getInstance().subtractTotalFileNum(walNode.getFileNum()); |
| } |
| } finally { |
| nodesLock.unlock(); |
| } |
| } |
| |
| @Override |
| public List<WALNode> getNodesSnapshot() { |
| List<WALNode> snapshot; |
| nodesLock.lock(); |
| try { |
| snapshot = new ArrayList<>(identifier2Nodes.values()); |
| } finally { |
| nodesLock.unlock(); |
| } |
| return snapshot; |
| } |
| |
| @Override |
| public int getNodesNum() { |
| return identifier2Nodes.size(); |
| } |
| |
| @Override |
| public void clear() { |
| nodesLock.lock(); |
| try { |
| for (WALNode walNode : identifier2Nodes.values()) { |
| walNode.close(); |
| } |
| identifier2Nodes.clear(); |
| } finally { |
| nodesLock.unlock(); |
| } |
| } |
| } |