navneet1v commented on code in PR #14178: URL: https://github.com/apache/lucene/pull/14178#discussion_r1934818584
########## lucene/sandbox/src/java22/org/apache/lucene/sandbox/codecs/faiss/LibFaissC.java: ########## @@ -0,0 +1,268 @@ +/* + * 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.faiss; + +import static java.lang.foreign.ValueLayout.ADDRESS; +import static java.lang.foreign.ValueLayout.JAVA_FLOAT; +import static java.lang.foreign.ValueLayout.JAVA_INT; +import static java.lang.foreign.ValueLayout.JAVA_LONG; + +import java.lang.foreign.Arena; +import java.lang.foreign.FunctionDescriptor; +import java.lang.foreign.Linker; +import java.lang.foreign.MemoryLayout; +import java.lang.foreign.MemorySegment; +import java.lang.foreign.SymbolLookup; +import java.lang.invoke.MethodHandle; +import java.nio.ByteOrder; +import java.nio.FloatBuffer; +import java.util.Locale; +import org.apache.lucene.index.FloatVectorValues; +import org.apache.lucene.index.KnnVectorValues; +import org.apache.lucene.index.VectorSimilarityFunction; +import org.apache.lucene.search.KnnCollector; +import org.apache.lucene.util.Bits; + +public final class LibFaissC { + public static final String LIBRARY_VERSION = "1.9.0"; + + static { + try { + System.loadLibrary("faiss_c"); + } catch (UnsatisfiedLinkError e) { + throw new RuntimeException( + "Shared library not found, build the Faiss C_API from https://github.com/facebookresearch/faiss/blob/main/c_api/INSTALL.md " + + "and link it (along with all dependencies) to the library path " + + "(-Djava.library.path JVM argument or $LD_LIBRARY_PATH environment variable)", + e); + } + checkLibraryVersion(); + } + + private LibFaissC() {} + + private static MethodHandle getMethodHandle( + String functionName, MemoryLayout resLayout, MemoryLayout... argLayouts) { + return Linker.nativeLinker() + .downcallHandle( + SymbolLookup.loaderLookup().find(functionName).orElseThrow(), + FunctionDescriptor.of(resLayout, argLayouts)); + } + + private static void checkLibraryVersion() { + MethodHandle getVersion = getMethodHandle("faiss_get_version", ADDRESS); + String actualVersion = callAndGetString(getVersion); + if (LIBRARY_VERSION.equals(actualVersion) == false) { + throw new UnsupportedOperationException( + String.format( + Locale.ROOT, + "Expected Faiss library version %s, found %s", + LIBRARY_VERSION, + actualVersion)); + } + } + + private static final MethodHandle FREE_INDEX = + getMethodHandle("faiss_Index_free", JAVA_INT, ADDRESS); + + public static void freeIndex(MemorySegment indexPointer) { + callAndHandleError(FREE_INDEX, indexPointer); + } + + private static final MethodHandle FREE_PARAMETER_SPACE = + getMethodHandle("faiss_ParameterSpace_free", JAVA_INT, ADDRESS); + + private static void freeParameterSpace(MemorySegment parameterSpacePointer) { + callAndHandleError(FREE_PARAMETER_SPACE, parameterSpacePointer); + } + + private static final MethodHandle INDEX_FACTORY = + getMethodHandle("faiss_index_factory", JAVA_INT, ADDRESS, JAVA_INT, ADDRESS, JAVA_INT); + + private static final MethodHandle PARAMETER_SPACE_NEW = + getMethodHandle("faiss_ParameterSpace_new", JAVA_INT, ADDRESS); + + private static final MethodHandle SET_INDEX_PARAMETERS = + getMethodHandle( + "faiss_ParameterSpace_set_index_parameters", JAVA_INT, ADDRESS, ADDRESS, ADDRESS); + + private static final MethodHandle INDEX_IS_TRAINED = + getMethodHandle("faiss_Index_is_trained", JAVA_INT, ADDRESS); + + private static final MethodHandle INDEX_TRAIN = + getMethodHandle("faiss_Index_train", JAVA_INT, ADDRESS, JAVA_LONG, ADDRESS); + + private static final MethodHandle INDEX_ADD = + getMethodHandle("faiss_Index_add", JAVA_INT, ADDRESS, JAVA_LONG, ADDRESS); + + public record Index(MemorySegment indexPointer, int[] ordToDoc) {} + + public static Index createIndex( + String description, + String indexParams, + VectorSimilarityFunction function, + FloatVectorValues floatVectorValues) { + + try (Arena temp = Arena.ofConfined()) { + int size = floatVectorValues.size(); + int dimension = floatVectorValues.dimension(); + + // Mapped from faiss/MetricType.h + int metric = + switch (function) { + case DOT_PRODUCT -> 0; + case EUCLIDEAN -> 1; + default -> throw new UnsupportedOperationException("metric type not supported"); + }; + + // Create an index + MemorySegment pointer = temp.allocate(ADDRESS); + callAndHandleError(INDEX_FACTORY, pointer, dimension, temp.allocateFrom(description), metric); Review Comment: > there is an index in faiss called as IndexIDMap, that can wrap any Faiss index which can be used here to avoid having another ordToDoc array. Faiss internally maintains that mapping and will only give you the docIds as results on what you have passed during construction. See if we want to use that. FYI opensearch actually uses that. :) I see that you have already mentioned it in your description here: `Currently the ordinal -> doc id mapping is stored in Lucene and looked up at the end (can be done in Faiss using an IDMap, needs some investigation)` . Please ignore this comment. -- 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