path: root/core/src/test/java/org/elasticsearch/indices/cache/query/IndicesQueryCacheTests.java

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 * 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,
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 * "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
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package org.elasticsearch.indices.cache.query;

import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.search.ConstantScoreScorer;
import org.apache.lucene.search.ConstantScoreWeight;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.QueryCachingPolicy;
import org.apache.lucene.search.Scorer;
import org.apache.lucene.search.Weight;
import org.apache.lucene.store.Directory;
import org.apache.lucene.util.IOUtils;
import org.elasticsearch.common.lucene.index.ElasticsearchDirectoryReader;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.index.Index;
import org.elasticsearch.index.cache.query.QueryCacheStats;
import org.elasticsearch.index.shard.ShardId;
import org.elasticsearch.test.ESTestCase;

import java.io.IOException;

public class IndicesQueryCacheTests extends ESTestCase {

    private static class DummyQuery extends Query {

        private final int id;

        DummyQuery(int id) {
            this.id = id;
        }

        @Override
        public boolean equals(Object obj) {
            return super.equals(obj) && id == ((DummyQuery) obj).id;
        }

        @Override
        public int hashCode() {
            return 31 * super.hashCode() + id;
        }

        @Override
        public String toString(String field) {
            return "dummy";
        }

        @Override
        public Weight createWeight(IndexSearcher searcher, boolean needsScores)
                throws IOException {
            return new ConstantScoreWeight(this) {
                @Override
                public Scorer scorer(LeafReaderContext context) throws IOException {
                    return new ConstantScoreScorer(this, score(), DocIdSetIterator.all(context.reader().maxDoc()));
                }
            };
        }

    }

    public void testBasics() throws IOException {
        Directory dir = newDirectory();
        IndexWriter w = new IndexWriter(dir, newIndexWriterConfig());
        w.addDocument(new Document());
        DirectoryReader r = DirectoryReader.open(w, false);
        w.close();
        ShardId shard = new ShardId("index", "_na_", 0);
        r = ElasticsearchDirectoryReader.wrap(r, shard);
        IndexSearcher s = new IndexSearcher(r);
        s.setQueryCachingPolicy(QueryCachingPolicy.ALWAYS_CACHE);

        Settings settings = Settings.builder()
                .put(IndicesQueryCache.INDICES_CACHE_QUERY_COUNT_SETTING.getKey(), 10)
                .build();
        IndicesQueryCache cache = new IndicesQueryCache(settings);
        s.setQueryCache(cache);

        QueryCacheStats stats = cache.getStats(shard);
        assertEquals(0L, stats.getCacheSize());
        assertEquals(0L, stats.getCacheCount());
        assertEquals(0L, stats.getHitCount());
        assertEquals(0L, stats.getMissCount());

        assertEquals(1, s.count(new DummyQuery(0)));

        stats = cache.getStats(shard);
        assertEquals(1L, stats.getCacheSize());
        assertEquals(1L, stats.getCacheCount());
        assertEquals(0L, stats.getHitCount());
        assertEquals(1L, stats.getMissCount());

        for (int i = 1; i < 20; ++i) {
            assertEquals(1, s.count(new DummyQuery(i)));
        }

        stats = cache.getStats(shard);
        assertEquals(10L, stats.getCacheSize());
        assertEquals(20L, stats.getCacheCount());
        assertEquals(0L, stats.getHitCount());
        assertEquals(20L, stats.getMissCount());

        s.count(new DummyQuery(10));

        stats = cache.getStats(shard);
        assertEquals(10L, stats.getCacheSize());
        assertEquals(20L, stats.getCacheCount());
        assertEquals(1L, stats.getHitCount());
        assertEquals(20L, stats.getMissCount());

        IOUtils.close(r, dir);

        // got emptied, but no changes to other metrics
        stats = cache.getStats(shard);
        assertEquals(0L, stats.getCacheSize());
        assertEquals(20L, stats.getCacheCount());
        assertEquals(1L, stats.getHitCount());
        assertEquals(20L, stats.getMissCount());

        cache.onClose(shard);

        // forgot everything
        stats = cache.getStats(shard);
        assertEquals(0L, stats.getCacheSize());
        assertEquals(0L, stats.getCacheCount());
        assertEquals(0L, stats.getHitCount());
        assertEquals(0L, stats.getMissCount());

        cache.close(); // this triggers some assertions
    }

    public void testTwoShards() throws IOException {
        Directory dir1 = newDirectory();
        IndexWriter w1 = new IndexWriter(dir1, newIndexWriterConfig());
        w1.addDocument(new Document());
        DirectoryReader r1 = DirectoryReader.open(w1, false);
        w1.close();
        ShardId shard1 = new ShardId("index", "_na_", 0);
        r1 = ElasticsearchDirectoryReader.wrap(r1, shard1);
        IndexSearcher s1 = new IndexSearcher(r1);
        s1.setQueryCachingPolicy(QueryCachingPolicy.ALWAYS_CACHE);

        Directory dir2 = newDirectory();
        IndexWriter w2 = new IndexWriter(dir2, newIndexWriterConfig());
        w2.addDocument(new Document());
        DirectoryReader r2 = DirectoryReader.open(w2, false);
        w2.close();
        ShardId shard2 = new ShardId("index", "_na_", 1);
        r2 = ElasticsearchDirectoryReader.wrap(r2, shard2);
        IndexSearcher s2 = new IndexSearcher(r2);
        s2.setQueryCachingPolicy(QueryCachingPolicy.ALWAYS_CACHE);

        Settings settings = Settings.builder()
                .put(IndicesQueryCache.INDICES_CACHE_QUERY_COUNT_SETTING.getKey(), 10)
                .build();
        IndicesQueryCache cache = new IndicesQueryCache(settings);
        s1.setQueryCache(cache);
        s2.setQueryCache(cache);

        assertEquals(1, s1.count(new DummyQuery(0)));

        QueryCacheStats stats1 = cache.getStats(shard1);
        assertEquals(1L, stats1.getCacheSize());
        assertEquals(1L, stats1.getCacheCount());
        assertEquals(0L, stats1.getHitCount());
        assertEquals(1L, stats1.getMissCount());

        QueryCacheStats stats2 = cache.getStats(shard2);
        assertEquals(0L, stats2.getCacheSize());
        assertEquals(0L, stats2.getCacheCount());
        assertEquals(0L, stats2.getHitCount());
        assertEquals(0L, stats2.getMissCount());

        assertEquals(1, s2.count(new DummyQuery(0)));

        stats1 = cache.getStats(shard1);
        assertEquals(1L, stats1.getCacheSize());
        assertEquals(1L, stats1.getCacheCount());
        assertEquals(0L, stats1.getHitCount());
        assertEquals(1L, stats1.getMissCount());

        stats2 = cache.getStats(shard2);
        assertEquals(1L, stats2.getCacheSize());
        assertEquals(1L, stats2.getCacheCount());
        assertEquals(0L, stats2.getHitCount());
        assertEquals(1L, stats2.getMissCount());

        for (int i = 0; i < 20; ++i) {
            assertEquals(1, s2.count(new DummyQuery(i)));
        }

        stats1 = cache.getStats(shard1);
        assertEquals(0L, stats1.getCacheSize()); // evicted
        assertEquals(1L, stats1.getCacheCount());
        assertEquals(0L, stats1.getHitCount());
        assertEquals(1L, stats1.getMissCount());

        stats2 = cache.getStats(shard2);
        assertEquals(10L, stats2.getCacheSize());
        assertEquals(20L, stats2.getCacheCount());
        assertEquals(1L, stats2.getHitCount());
        assertEquals(20L, stats2.getMissCount());

        IOUtils.close(r1, dir1);

        // no changes
        stats1 = cache.getStats(shard1);
        assertEquals(0L, stats1.getCacheSize());
        assertEquals(1L, stats1.getCacheCount());
        assertEquals(0L, stats1.getHitCount());
        assertEquals(1L, stats1.getMissCount());

        stats2 = cache.getStats(shard2);
        assertEquals(10L, stats2.getCacheSize());
        assertEquals(20L, stats2.getCacheCount());
        assertEquals(1L, stats2.getHitCount());
        assertEquals(20L, stats2.getMissCount());

        cache.onClose(shard1);

        // forgot everything about shard1
        stats1 = cache.getStats(shard1);
        assertEquals(0L, stats1.getCacheSize());
        assertEquals(0L, stats1.getCacheCount());
        assertEquals(0L, stats1.getHitCount());
        assertEquals(0L, stats1.getMissCount());

        stats2 = cache.getStats(shard2);
        assertEquals(10L, stats2.getCacheSize());
        assertEquals(20L, stats2.getCacheCount());
        assertEquals(1L, stats2.getHitCount());
        assertEquals(20L, stats2.getMissCount());

        IOUtils.close(r2, dir2);
        cache.onClose(shard2);

        // forgot everything about shard2
        stats1 = cache.getStats(shard1);
        assertEquals(0L, stats1.getCacheSize());
        assertEquals(0L, stats1.getCacheCount());
        assertEquals(0L, stats1.getHitCount());
        assertEquals(0L, stats1.getMissCount());

        stats2 = cache.getStats(shard2);
        assertEquals(0L, stats2.getCacheSize());
        assertEquals(0L, stats2.getCacheCount());
        assertEquals(0L, stats2.getHitCount());
        assertEquals(0L, stats2.getMissCount());

        cache.close(); // this triggers some assertions
    }

    // Make sure the cache behaves correctly when a segment that is associated
    // with an empty cache gets closed. In that particular case, the eviction
    // callback is called with a number of evicted entries equal to 0
    // see https://github.com/elastic/elasticsearch/issues/15043
    public void testStatsOnEviction() throws IOException {
        Directory dir1 = newDirectory();
        IndexWriter w1 = new IndexWriter(dir1, newIndexWriterConfig());
        w1.addDocument(new Document());
        DirectoryReader r1 = DirectoryReader.open(w1, false);
        w1.close();
        ShardId shard1 = new ShardId("index", "_na_", 0);
        r1 = ElasticsearchDirectoryReader.wrap(r1, shard1);
        IndexSearcher s1 = new IndexSearcher(r1);
        s1.setQueryCachingPolicy(QueryCachingPolicy.ALWAYS_CACHE);

        Directory dir2 = newDirectory();
        IndexWriter w2 = new IndexWriter(dir2, newIndexWriterConfig());
        w2.addDocument(new Document());
        DirectoryReader r2 = DirectoryReader.open(w2, false);
        w2.close();
        ShardId shard2 = new ShardId("index", "_na_", 1);
        r2 = ElasticsearchDirectoryReader.wrap(r2, shard2);
        IndexSearcher s2 = new IndexSearcher(r2);
        s2.setQueryCachingPolicy(QueryCachingPolicy.ALWAYS_CACHE);

        Settings settings = Settings.builder()
                .put(IndicesQueryCache.INDICES_CACHE_QUERY_COUNT_SETTING.getKey(), 10)
                .build();
        IndicesQueryCache cache = new IndicesQueryCache(settings);
        s1.setQueryCache(cache);
        s2.setQueryCache(cache);

        assertEquals(1, s1.count(new DummyQuery(0)));

        for (int i = 1; i <= 20; ++i) {
            assertEquals(1, s2.count(new DummyQuery(i)));
        }

        QueryCacheStats stats1 = cache.getStats(shard1);
        assertEquals(0L, stats1.getCacheSize());
        assertEquals(1L, stats1.getCacheCount());

        // this used to fail because we were evicting an empty cache on
        // the segment from r1
        IOUtils.close(r1, dir1);
        cache.onClose(shard1);

        IOUtils.close(r2, dir2);
        cache.onClose(shard2);

        cache.close(); // this triggers some assertions
    }

}