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WriteIndex.cpp
1 /**
2 * Copyright (c) Facebook, Inc. and its affiliates.
3 *
4 * This source code is licensed under the MIT license found in the
5 * LICENSE file in the root directory of this source tree.
6 */
7
8
9 #include "../../IndexIVFFlat.h"
10 #include "../../IndexIVFPQ.h"
11 #include "../../IndexFlat.h"
12 #include "../../index_io.h"
13 #include "../test/TestUtils.h"
14 #include <vector>
15 #include <gflags/gflags.h>
16
17 // For IVFPQ:
18 DEFINE_bool(ivfpq, false, "use IVFPQ encoding");
19 DEFINE_int32(codes, 4, "number of PQ codes per vector");
20 DEFINE_int32(bits_per_code, 8, "number of bits per PQ code");
21
22 // For IVFFlat:
23 DEFINE_bool(l2, true, "use L2 metric (versus IP metric)");
24 DEFINE_bool(ivfflat, false, "use IVF flat encoding");
25
26 // For both:
27 DEFINE_string(out, "/home/jhj/local/index.out", "index file for output");
28 DEFINE_int32(dim, 128, "vector dimension");
29 DEFINE_int32(num_coarse, 100, "number of coarse centroids");
30 DEFINE_int32(num, 100000, "total database size");
31 DEFINE_int32(num_train, -1, "number of database vecs to train on");
32
33 template <typename T>
34 void fillAndSave(T& index, int numTrain, int num, int dim) {
35 auto trainVecs = faiss::gpu::randVecs(numTrain, dim);
36 index.train(numTrain, trainVecs.data());
37
38 constexpr int kAddChunk = 1000000;
39
40 for (int i = 0; i < num; i += kAddChunk) {
41 int numRemaining = (num - i) < kAddChunk ? (num - i) : kAddChunk;
42 auto vecs = faiss::gpu::randVecs(numRemaining, dim);
43
44 printf("adding at %d: %d\n", i, numRemaining);
45 index.add(numRemaining, vecs.data());
46 }
47
48 faiss::write_index(&index, FLAGS_out.c_str());
49 }
50
51 int main(int argc, char** argv) {
52 gflags::ParseCommandLineFlags(&argc, &argv, true);
53
54 // Either ivfpq or ivfflat must be set
55 if ((FLAGS_ivfpq && FLAGS_ivfflat) ||
56 (!FLAGS_ivfpq && !FLAGS_ivfflat)) {
57 printf("must specify either ivfpq or ivfflat\n");
58 return 1;
59 }
60
61 auto dim = FLAGS_dim;
62 auto numCentroids = FLAGS_num_coarse;
63 auto num = FLAGS_num;
64 auto numTrain = FLAGS_num_train;
65 numTrain = numTrain == -1 ? std::max((num / 4), 1) : numTrain;
66 numTrain = std::min(num, numTrain);
67
68 if (FLAGS_ivfpq) {
69 faiss::IndexFlatL2 quantizer(dim);
70 faiss::IndexIVFPQ index(&quantizer, dim, numCentroids,
71 FLAGS_codes, FLAGS_bits_per_code);
72 index.verbose = true;
73
74 printf("IVFPQ: codes %d bits per code %d\n",
75 FLAGS_codes, FLAGS_bits_per_code);
76 printf("Lists: %d\n", numCentroids);
77 printf("Database: dim %d num vecs %d trained on %d\n", dim, num, numTrain);
78 printf("output file: %s\n", FLAGS_out.c_str());
79
80 fillAndSave(index, numTrain, num, dim);
81 } else if (FLAGS_ivfflat) {
82 faiss::IndexFlatL2 quantizerL2(dim);
83 faiss::IndexFlatIP quantizerIP(dim);
84
85 faiss::IndexFlat* quantizer = FLAGS_l2 ?
86 (faiss::IndexFlat*) &quantizerL2 :
87 (faiss::IndexFlat*) &quantizerIP;
88
89 faiss::IndexIVFFlat index(quantizer, dim, numCentroids,
90 FLAGS_l2 ? faiss::METRIC_L2 :
91 faiss::METRIC_INNER_PRODUCT);
92
93 printf("IVFFlat: metric %s\n", FLAGS_l2 ? "L2" : "IP");
94 printf("Lists: %d\n", numCentroids);
95 printf("Database: dim %d num vecs %d trained on %d\n", dim, num, numTrain);
96 printf("output file: %s\n", FLAGS_out.c_str());
97
98 fillAndSave(index, numTrain, num, dim);
99 }
100
101 return 0;
102 }
faiss::IndexFlat
Definition: IndexFlat.h:21
faiss::IndexFlatL2
Definition: IndexFlat.h:77
faiss::IndexIVFFlat
Definition: IndexIVFFlat.h:24
faiss::IndexFlatIP
Definition: IndexFlat.h:71
faiss::IndexIVFPQ
Definition: IndexIVFPQ.h:34