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/* * Licensed to Elasticsearch under one or more contributor * license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright * ownership. Elasticsearch 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.elasticsearch.index.merge.policy; import org.apache.lucene.index.LogDocMergePolicy; import org.apache.lucene.index.MergePolicy; import org.apache.lucene.index.SegmentInfos; import org.elasticsearch.ElasticsearchException; import org.elasticsearch.common.Preconditions; import org.elasticsearch.common.inject.Inject; import org.elasticsearch.common.settings.Settings; import org.elasticsearch.index.settings.IndexSettingsService; import org.elasticsearch.index.store.Store; import java.io.IOException; import java.util.Set; import java.util.concurrent.CopyOnWriteArraySet; /** * */ public class LogDocMergePolicyProvider extends AbstractMergePolicyProvider<LogDocMergePolicy> { private final IndexSettingsService indexSettingsService; private volatile int minMergeDocs; private volatile int maxMergeDocs; private volatile int mergeFactor; private final boolean calibrateSizeByDeletes; private boolean asyncMerge; private final Set<CustomLogDocMergePolicy> policies = new CopyOnWriteArraySet<CustomLogDocMergePolicy>(); private final ApplySettings applySettings = new ApplySettings(); @Inject public LogDocMergePolicyProvider(Store store, IndexSettingsService indexSettingsService) { super(store); Preconditions.checkNotNull(store, "Store must be provided to merge policy"); this.indexSettingsService = indexSettingsService; this.minMergeDocs = componentSettings.getAsInt("min_merge_docs", LogDocMergePolicy.DEFAULT_MIN_MERGE_DOCS); this.maxMergeDocs = componentSettings.getAsInt("max_merge_docs", LogDocMergePolicy.DEFAULT_MAX_MERGE_DOCS); this.mergeFactor = componentSettings.getAsInt("merge_factor", LogDocMergePolicy.DEFAULT_MERGE_FACTOR); this.calibrateSizeByDeletes = componentSettings.getAsBoolean("calibrate_size_by_deletes", true); this.asyncMerge = indexSettings.getAsBoolean("index.merge.async", true); logger.debug( "using [log_doc] merge policy with merge_factor[{}], min_merge_docs[{}], max_merge_docs[{}], calibrate_size_by_deletes[{}], async_merge[{}]", mergeFactor, minMergeDocs, maxMergeDocs, calibrateSizeByDeletes, asyncMerge); indexSettingsService.addListener(applySettings); } @Override public void close() throws ElasticsearchException { indexSettingsService.removeListener(applySettings); } @Override public LogDocMergePolicy newMergePolicy() { CustomLogDocMergePolicy mergePolicy; if (asyncMerge) { mergePolicy = new EnableMergeLogDocMergePolicy(this); } else { mergePolicy = new CustomLogDocMergePolicy(this); } mergePolicy.setMinMergeDocs(minMergeDocs); mergePolicy.setMaxMergeDocs(maxMergeDocs); mergePolicy.setMergeFactor(mergeFactor); mergePolicy.setCalibrateSizeByDeletes(calibrateSizeByDeletes); mergePolicy.setNoCFSRatio(noCFSRatio); policies.add(mergePolicy); return mergePolicy; } public static final String INDEX_MERGE_POLICY_MIN_MERGE_DOCS = "index.merge.policy.min_merge_docs"; public static final String INDEX_MERGE_POLICY_MAX_MERGE_DOCS = "index.merge.policy.max_merge_docs"; public static final String INDEX_MERGE_POLICY_MERGE_FACTOR = "index.merge.policy.merge_factor"; class ApplySettings implements IndexSettingsService.Listener { @Override public void onRefreshSettings(Settings settings) { int minMergeDocs = settings.getAsInt(INDEX_MERGE_POLICY_MIN_MERGE_DOCS, LogDocMergePolicyProvider.this.minMergeDocs); if (minMergeDocs != LogDocMergePolicyProvider.this.minMergeDocs) { logger.info("updating min_merge_docs from [{}] to [{}]", LogDocMergePolicyProvider.this.minMergeDocs, minMergeDocs); LogDocMergePolicyProvider.this.minMergeDocs = minMergeDocs; for (CustomLogDocMergePolicy policy : policies) { policy.setMinMergeDocs(minMergeDocs); } } int maxMergeDocs = settings.getAsInt(INDEX_MERGE_POLICY_MAX_MERGE_DOCS, LogDocMergePolicyProvider.this.maxMergeDocs); if (maxMergeDocs != LogDocMergePolicyProvider.this.maxMergeDocs) { logger.info("updating max_merge_docs from [{}] to [{}]", LogDocMergePolicyProvider.this.maxMergeDocs, maxMergeDocs); LogDocMergePolicyProvider.this.maxMergeDocs = maxMergeDocs; for (CustomLogDocMergePolicy policy : policies) { policy.setMaxMergeDocs(maxMergeDocs); } } int mergeFactor = settings.getAsInt(INDEX_MERGE_POLICY_MERGE_FACTOR, LogDocMergePolicyProvider.this.mergeFactor); if (mergeFactor != LogDocMergePolicyProvider.this.mergeFactor) { logger.info("updating merge_factor from [{}] to [{}]", LogDocMergePolicyProvider.this.mergeFactor, mergeFactor); LogDocMergePolicyProvider.this.mergeFactor = mergeFactor; for (CustomLogDocMergePolicy policy : policies) { policy.setMergeFactor(mergeFactor); } } final double noCFSRatio = parseNoCFSRatio(settings.get(INDEX_COMPOUND_FORMAT, Double.toString(LogDocMergePolicyProvider.this.noCFSRatio))); final boolean compoundFormat = noCFSRatio != 0.0; if (noCFSRatio != LogDocMergePolicyProvider.this.noCFSRatio) { logger.info("updating index.compound_format from [{}] to [{}]", formatNoCFSRatio(LogDocMergePolicyProvider.this.noCFSRatio), formatNoCFSRatio(noCFSRatio)); LogDocMergePolicyProvider.this.noCFSRatio = noCFSRatio; for (CustomLogDocMergePolicy policy : policies) { policy.setNoCFSRatio(noCFSRatio); } } } } public static class CustomLogDocMergePolicy extends LogDocMergePolicy { private final LogDocMergePolicyProvider provider; public CustomLogDocMergePolicy(LogDocMergePolicyProvider provider) { super(); this.provider = provider; } @Override public void close() { super.close(); provider.policies.remove(this); } } public static class EnableMergeLogDocMergePolicy extends CustomLogDocMergePolicy { public EnableMergeLogDocMergePolicy(LogDocMergePolicyProvider provider) { super(provider); } @Override public MergeSpecification findMerges(MergeTrigger trigger, SegmentInfos infos) throws IOException { // we don't enable merges while indexing documents, we do them in the background if (trigger == MergeTrigger.SEGMENT_FLUSH) { return null; } return super.findMerges(trigger, infos); } @Override public MergePolicy clone() { // Lucene IW makes a clone internally but since we hold on to this instance // the clone will just be the identity. return this; } } }