benwtrent commented on code in PR #13288: URL: https://github.com/apache/lucene/pull/13288#discussion_r1560987003
########## lucene/sandbox/src/java/org/apache/lucene/sandbox/codecs/bitvectors/HnswBitVectorsFormat.java: ########## @@ -0,0 +1,211 @@ +/* + * 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.lucene.sandbox.codecs.bitvectors; + +import static org.apache.lucene.codecs.lucene99.Lucene99HnswVectorsFormat.DEFAULT_BEAM_WIDTH; +import static org.apache.lucene.codecs.lucene99.Lucene99HnswVectorsFormat.DEFAULT_MAX_CONN; +import static org.apache.lucene.codecs.lucene99.Lucene99HnswVectorsFormat.DEFAULT_NUM_MERGE_WORKER; +import static org.apache.lucene.codecs.lucene99.Lucene99HnswVectorsFormat.MAXIMUM_BEAM_WIDTH; +import static org.apache.lucene.codecs.lucene99.Lucene99HnswVectorsFormat.MAXIMUM_MAX_CONN; + +import java.io.IOException; +import java.util.concurrent.ExecutorService; +import org.apache.lucene.codecs.KnnFieldVectorsWriter; +import org.apache.lucene.codecs.KnnVectorsFormat; +import org.apache.lucene.codecs.KnnVectorsReader; +import org.apache.lucene.codecs.KnnVectorsWriter; +import org.apache.lucene.codecs.hnsw.FlatFieldVectorsWriter; +import org.apache.lucene.codecs.hnsw.FlatVectorsFormat; +import org.apache.lucene.codecs.hnsw.FlatVectorsWriter; +import org.apache.lucene.codecs.lucene99.Lucene99FlatVectorsFormat; +import org.apache.lucene.codecs.lucene99.Lucene99HnswVectorsFormat; +import org.apache.lucene.codecs.lucene99.Lucene99HnswVectorsReader; +import org.apache.lucene.codecs.lucene99.Lucene99HnswVectorsWriter; +import org.apache.lucene.index.FieldInfo; +import org.apache.lucene.index.MergeState; +import org.apache.lucene.index.SegmentReadState; +import org.apache.lucene.index.SegmentWriteState; +import org.apache.lucene.index.Sorter; +import org.apache.lucene.index.VectorEncoding; +import org.apache.lucene.search.TaskExecutor; +import org.apache.lucene.util.hnsw.CloseableRandomVectorScorerSupplier; +import org.apache.lucene.util.hnsw.HnswGraph; + +/** + * Encodes bit vector values into an associated graph connecting the documents having values. The + * graph is used to power HNSW search. The format consists of two files, and uses {@link + * Lucene99FlatVectorsFormat} to store the actual vectors, but with a custom scorer implementation: + * For details on graph storage and file extensions, see {@link Lucene99HnswVectorsFormat}. + * + * @lucene.experimental + */ +public final class HnswBitVectorsFormat extends KnnVectorsFormat { + + /** + * Controls how many of the nearest neighbor candidates are connected to the new node. Defaults to + * {@link Lucene99HnswVectorsFormat#DEFAULT_MAX_CONN}. See {@link HnswGraph} for more details. + */ + private final int maxConn; + + /** + * The number of candidate neighbors to track while searching the graph for each newly inserted + * node. Defaults to {@link Lucene99HnswVectorsFormat#DEFAULT_BEAM_WIDTH}. See {@link HnswGraph} + * for details. + */ + private final int beamWidth; + + /** The format for storing, reading, merging vectors on disk */ + private final FlatVectorsFormat flatVectorsFormat; + + private final int numMergeWorkers; + private final TaskExecutor mergeExec; + + /** Constructs a format using default graph construction parameters */ + public HnswBitVectorsFormat() { + this(DEFAULT_MAX_CONN, DEFAULT_BEAM_WIDTH, DEFAULT_NUM_MERGE_WORKER, null); + } + + /** + * Constructs a format using the given graph construction parameters. + * + * @param maxConn the maximum number of connections to a node in the HNSW graph + * @param beamWidth the size of the queue maintained during graph construction. + */ + public HnswBitVectorsFormat(int maxConn, int beamWidth) { + this(maxConn, beamWidth, DEFAULT_NUM_MERGE_WORKER, null); + } + + /** + * Constructs a format using the given graph construction parameters and scalar quantization. + * + * @param maxConn the maximum number of connections to a node in the HNSW graph + * @param beamWidth the size of the queue maintained during graph construction. + * @param numMergeWorkers number of workers (threads) that will be used when doing merge. If + * larger than 1, a non-null {@link ExecutorService} must be passed as mergeExec + * @param mergeExec the {@link ExecutorService} that will be used by ALL vector writers that are + * generated by this format to do the merge + */ + public HnswBitVectorsFormat( + int maxConn, int beamWidth, int numMergeWorkers, ExecutorService mergeExec) { + super("Lucene99HnswBitVectorsFormat"); + if (maxConn <= 0 || maxConn > MAXIMUM_MAX_CONN) { + throw new IllegalArgumentException( + "maxConn must be positive and less than or equal to " + + MAXIMUM_MAX_CONN + + "; maxConn=" + + maxConn); + } + if (beamWidth <= 0 || beamWidth > MAXIMUM_BEAM_WIDTH) { + throw new IllegalArgumentException( + "beamWidth must be positive and less than or equal to " + + MAXIMUM_BEAM_WIDTH + + "; beamWidth=" + + beamWidth); + } + this.maxConn = maxConn; + this.beamWidth = beamWidth; + if (numMergeWorkers == 1 && mergeExec != null) { + throw new IllegalArgumentException( + "No executor service is needed as we'll use single thread to merge"); + } + this.numMergeWorkers = numMergeWorkers; + if (mergeExec != null) { + this.mergeExec = new TaskExecutor(mergeExec); + } else { + this.mergeExec = null; + } + this.flatVectorsFormat = new Lucene99FlatVectorsFormat(new OnHeapFlatBitVectorsScorer()); Review Comment: > This would avoid the copy and the need to wrap the reader/writer? Maybe I don't understand. From what I can tell, the only thing this would give us is not copying the ctor validations. We would still need the new class, and the new writer as it validates only BYTE vectors are written. -- 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. To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org
