faiss/index_io.cpp

1294 lines
43 KiB
C++

/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD+Patents license found in the
* LICENSE file in the root directory of this source tree.
*/
// -*- c++ -*-
#include "index_io.h"
#include <cstdio>
#include <cstdlib>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "FaissAssert.h"
#include "AuxIndexStructures.h"
#include "IndexFlat.h"
#include "VectorTransform.h"
#include "IndexLSH.h"
#include "IndexPQ.h"
#include "IndexIVF.h"
#include "IndexIVFPQ.h"
#include "IndexIVFFlat.h"
#include "MetaIndexes.h"
#include "IndexScalarQuantizer.h"
#include "IndexHNSW.h"
#include "OnDiskInvertedLists.h"
#include "IndexBinaryFlat.h"
#include "IndexBinaryFromFloat.h"
#include "IndexBinaryHNSW.h"
#include "IndexBinaryIVF.h"
/*************************************************************
* The I/O format is the content of the class. For objects that are
* inherited, like Index, a 4-character-code (fourcc) indicates which
* child class this is an instance of.
*
* In this case, the fields of the parent class are written first,
* then the ones for the child classes. Note that this requires
* classes to be serialized to have a constructor without parameters,
* so that the fields can be filled in later. The default constructor
* should set reasonable defaults for all fields.
*
* The fourccs are assigned arbitrarily. When the class changed (added
* or deprecated fields), the fourcc can be replaced. New code should
* be able to read the old fourcc and fill in new classes.
*
* TODO: serialization to strings for use in Python pickle or Torch
* serialization.
*
* TODO: in this file, the read functions that encouter errors may
* leak memory.
**************************************************************/
namespace faiss {
static uint32_t fourcc (const char sx[4]) {
assert(4 == strlen(sx));
const unsigned char *x = (unsigned char*)sx;
return x[0] | x[1] << 8 | x[2] << 16 | x[3] << 24;
}
/*************************************************************
* I/O macros
*
* we use macros so that we have a line number to report in abort
* (). This makes debugging a lot easier. The IOReader or IOWriter is
* always called f and thus is not passed in as a macro parameter.
**************************************************************/
#define WRITEANDCHECK(ptr, n) { \
size_t ret = (*f)(ptr, sizeof(*(ptr)), n); \
FAISS_THROW_IF_NOT_FMT(ret == (n), \
"write error in %s: %ld != %ld (%s)", \
f->name.c_str(), ret, size_t(n), strerror(errno)); \
}
#define READANDCHECK(ptr, n) { \
size_t ret = (*f)(ptr, sizeof(*(ptr)), n); \
FAISS_THROW_IF_NOT_FMT(ret == (n), \
"read error in %s: %ld != %ld (%s)", \
f->name.c_str(), ret, size_t(n), strerror(errno)); \
}
#define WRITE1(x) WRITEANDCHECK(&(x), 1)
#define READ1(x) READANDCHECK(&(x), 1)
#define WRITEVECTOR(vec) { \
size_t size = (vec).size (); \
WRITEANDCHECK (&size, 1); \
WRITEANDCHECK ((vec).data (), size); \
}
// will fail if we write 256G of data at once...
#define READVECTOR(vec) { \
long size; \
READANDCHECK (&size, 1); \
FAISS_THROW_IF_NOT (size >= 0 && size < (1L << 40)); \
(vec).resize (size); \
READANDCHECK ((vec).data (), size); \
}
struct ScopeFileCloser {
FILE *f;
ScopeFileCloser (FILE *f): f (f) {}
~ScopeFileCloser () {fclose (f); }
};
namespace {
struct FileIOReader: IOReader {
FILE *f = nullptr;
bool need_close = false;
FileIOReader(FILE *rf): f(rf) {}
FileIOReader(const char * fname)
{
name = fname;
f = fopen(fname, "rb");
FAISS_THROW_IF_NOT_FMT (
f, "could not open %s for reading: %s",
fname, strerror(errno));
need_close = true;
}
~FileIOReader() {
if (need_close) {
int ret = fclose(f);
FAISS_THROW_IF_NOT_FMT (
ret == 0, "file %s close error: %s",
name.c_str(), strerror(errno));
}
}
size_t operator()(
void *ptr, size_t size, size_t nitems) override {
return fread(ptr, size, nitems, f);
}
int fileno() override {
return ::fileno (f);
}
};
struct FileIOWriter: IOWriter {
FILE *f = nullptr;
bool need_close = false;
FileIOWriter(FILE *wf): f(wf) {}
FileIOWriter(const char * fname)
{
name = fname;
f = fopen(fname, "wb");
FAISS_THROW_IF_NOT_FMT (
f, "could not open %s for writing: %s",
fname, strerror(errno));
need_close = true;
}
~FileIOWriter() {
if (need_close) {
int ret = fclose(f);
FAISS_THROW_IF_NOT_FMT (
ret == 0, "file %s close error: %s",
name.c_str(), strerror(errno));
}
}
size_t operator()(
const void *ptr, size_t size, size_t nitems) override {
return fwrite(ptr, size, nitems, f);
}
int fileno() override {
return ::fileno (f);
}
};
} // namespace
/*************************************************************
* Write
**************************************************************/
static void write_index_header (const Index *idx, IOWriter *f) {
WRITE1 (idx->d);
WRITE1 (idx->ntotal);
Index::idx_t dummy = 1 << 20;
WRITE1 (dummy);
WRITE1 (dummy);
WRITE1 (idx->is_trained);
WRITE1 (idx->metric_type);
}
void write_VectorTransform (const VectorTransform *vt, IOWriter *f) {
if (const LinearTransform * lt =
dynamic_cast < const LinearTransform *> (vt)) {
if (dynamic_cast<const RandomRotationMatrix *>(lt)) {
uint32_t h = fourcc ("rrot");
WRITE1 (h);
} else if (const PCAMatrix * pca =
dynamic_cast<const PCAMatrix *>(lt)) {
uint32_t h = fourcc ("PcAm");
WRITE1 (h);
WRITE1 (pca->eigen_power);
WRITE1 (pca->random_rotation);
WRITE1 (pca->balanced_bins);
WRITEVECTOR (pca->mean);
WRITEVECTOR (pca->eigenvalues);
WRITEVECTOR (pca->PCAMat);
} else {
// generic LinearTransform (includes OPQ)
uint32_t h = fourcc ("LTra");
WRITE1 (h);
}
WRITE1 (lt->have_bias);
WRITEVECTOR (lt->A);
WRITEVECTOR (lt->b);
} else if (const RemapDimensionsTransform *rdt =
dynamic_cast<const RemapDimensionsTransform *>(vt)) {
uint32_t h = fourcc ("RmDT");
WRITE1 (h);
WRITEVECTOR (rdt->map);
} else if (const NormalizationTransform *nt =
dynamic_cast<const NormalizationTransform *>(vt)) {
uint32_t h = fourcc ("VNrm");
WRITE1 (h);
WRITE1 (nt->norm);
} else {
FAISS_THROW_MSG ("cannot serialize this");
}
// common fields
WRITE1 (vt->d_in);
WRITE1 (vt->d_out);
WRITE1 (vt->is_trained);
}
void write_ProductQuantizer (const ProductQuantizer *pq, IOWriter *f) {
WRITE1 (pq->d);
WRITE1 (pq->M);
WRITE1 (pq->nbits);
WRITEVECTOR (pq->centroids);
}
static void write_ScalarQuantizer (
const ScalarQuantizer *ivsc, IOWriter *f) {
WRITE1 (ivsc->qtype);
WRITE1 (ivsc->rangestat);
WRITE1 (ivsc->rangestat_arg);
WRITE1 (ivsc->d);
WRITE1 (ivsc->code_size);
WRITEVECTOR (ivsc->trained);
}
void write_InvertedLists (const InvertedLists *ils, IOWriter *f) {
if (ils == nullptr) {
uint32_t h = fourcc ("il00");
WRITE1 (h);
} else if (const auto & ails =
dynamic_cast<const ArrayInvertedLists *>(ils)) {
uint32_t h = fourcc ("ilar");
WRITE1 (h);
WRITE1 (ails->nlist);
WRITE1 (ails->code_size);
// here we store either as a full or a sparse data buffer
size_t n_non0 = 0;
for (size_t i = 0; i < ails->nlist; i++) {
if (ails->ids[i].size() > 0)
n_non0++;
}
if (n_non0 > ails->nlist / 2) {
uint32_t list_type = fourcc("full");
WRITE1 (list_type);
std::vector<size_t> sizes;
for (size_t i = 0; i < ails->nlist; i++) {
sizes.push_back (ails->ids[i].size());
}
WRITEVECTOR (sizes);
} else {
int list_type = fourcc("sprs"); // sparse
WRITE1 (list_type);
std::vector<size_t> sizes;
for (size_t i = 0; i < ails->nlist; i++) {
size_t n = ails->ids[i].size();
if (n > 0) {
sizes.push_back (i);
sizes.push_back (n);
}
}
WRITEVECTOR (sizes);
}
// make a single contiguous data buffer (useful for mmapping)
for (size_t i = 0; i < ails->nlist; i++) {
size_t n = ails->ids[i].size();
if (n > 0) {
WRITEANDCHECK (ails->codes[i].data(), n * ails->code_size);
WRITEANDCHECK (ails->ids[i].data(), n);
}
}
} else if (const auto & od =
dynamic_cast<const OnDiskInvertedLists *>(ils)) {
uint32_t h = fourcc ("ilod");
WRITE1 (h);
WRITE1 (ils->nlist);
WRITE1 (ils->code_size);
// this is a POD object
WRITEVECTOR (od->lists);
{
std::vector<OnDiskInvertedLists::Slot> v(
od->slots.begin(), od->slots.end());
WRITEVECTOR(v);
}
{
std::vector<char> x(od->filename.begin(), od->filename.end());
WRITEVECTOR(x);
}
WRITE1(od->totsize);
} else {
fprintf(stderr, "WARN! write_InvertedLists: unsupported invlist type, "
"saving null invlist\n");
uint32_t h = fourcc ("il00");
WRITE1 (h);
}
}
void write_ProductQuantizer (const ProductQuantizer*pq, const char *fname) {
FileIOWriter writer(fname);
write_ProductQuantizer (pq, &writer);
}
static void write_HNSW (const HNSW *hnsw, IOWriter *f) {
WRITEVECTOR (hnsw->assign_probas);
WRITEVECTOR (hnsw->cum_nneighbor_per_level);
WRITEVECTOR (hnsw->levels);
WRITEVECTOR (hnsw->offsets);
WRITEVECTOR (hnsw->neighbors);
WRITE1 (hnsw->entry_point);
WRITE1 (hnsw->max_level);
WRITE1 (hnsw->efConstruction);
WRITE1 (hnsw->efSearch);
WRITE1 (hnsw->upper_beam);
}
static void write_ivf_header (const IndexIVF *ivf, IOWriter *f) {
write_index_header (ivf, f);
WRITE1 (ivf->nlist);
WRITE1 (ivf->nprobe);
write_index (ivf->quantizer, f);
WRITE1 (ivf->maintain_direct_map);
WRITEVECTOR (ivf->direct_map);
}
void write_index (const Index *idx, IOWriter *f) {
if (const IndexFlat * idxf = dynamic_cast<const IndexFlat *> (idx)) {
uint32_t h = fourcc (
idxf->metric_type == METRIC_INNER_PRODUCT ? "IxFI" :
idxf->metric_type == METRIC_L2 ? "IxF2" : nullptr);
WRITE1 (h);
write_index_header (idx, f);
WRITEVECTOR (idxf->xb);
} else if(const IndexLSH * idxl = dynamic_cast<const IndexLSH *> (idx)) {
uint32_t h = fourcc ("IxHe");
WRITE1 (h);
write_index_header (idx, f);
WRITE1 (idxl->nbits);
WRITE1 (idxl->rotate_data);
WRITE1 (idxl->train_thresholds);
WRITEVECTOR (idxl->thresholds);
WRITE1 (idxl->bytes_per_vec);
write_VectorTransform (&idxl->rrot, f);
WRITEVECTOR (idxl->codes);
} else if(const IndexPQ * idxp = dynamic_cast<const IndexPQ *> (idx)) {
uint32_t h = fourcc ("IxPq");
WRITE1 (h);
write_index_header (idx, f);
write_ProductQuantizer (&idxp->pq, f);
WRITEVECTOR (idxp->codes);
// search params -- maybe not useful to store?
WRITE1 (idxp->search_type);
WRITE1 (idxp->encode_signs);
WRITE1 (idxp->polysemous_ht);
} else if(const Index2Layer * idxp =
dynamic_cast<const Index2Layer *> (idx)) {
uint32_t h = fourcc ("Ix2L");
WRITE1 (h);
write_index_header (idx, f);
write_index (idxp->q1.quantizer, f);
WRITE1 (idxp->q1.nlist);
WRITE1 (idxp->q1.quantizer_trains_alone);
write_ProductQuantizer (&idxp->pq, f);
WRITE1 (idxp->code_size_1);
WRITE1 (idxp->code_size_2);
WRITE1 (idxp->code_size);
WRITEVECTOR (idxp->codes);
} else if(const IndexScalarQuantizer * idxs =
dynamic_cast<const IndexScalarQuantizer *> (idx)) {
uint32_t h = fourcc ("IxSQ");
WRITE1 (h);
write_index_header (idx, f);
write_ScalarQuantizer (&idxs->sq, f);
WRITEVECTOR (idxs->codes);
} else if(const IndexIVFFlatDedup * ivfl =
dynamic_cast<const IndexIVFFlatDedup *> (idx)) {
uint32_t h = fourcc ("IwFd");
WRITE1 (h);
write_ivf_header (ivfl, f);
{
std::vector<Index::idx_t> tab (2 * ivfl->instances.size());
long i = 0;
for (auto it = ivfl->instances.begin();
it != ivfl->instances.end(); ++it) {
tab[i++] = it->first;
tab[i++] = it->second;
}
WRITEVECTOR (tab);
}
write_InvertedLists (ivfl->invlists, f);
} else if(const IndexIVFFlat * ivfl =
dynamic_cast<const IndexIVFFlat *> (idx)) {
uint32_t h = fourcc ("IwFl");
WRITE1 (h);
write_ivf_header (ivfl, f);
write_InvertedLists (ivfl->invlists, f);
} else if(const IndexIVFScalarQuantizer * ivsc =
dynamic_cast<const IndexIVFScalarQuantizer *> (idx)) {
uint32_t h = fourcc ("IwSQ");
WRITE1 (h);
write_ivf_header (ivsc, f);
write_ScalarQuantizer (&ivsc->sq, f);
WRITE1 (ivsc->code_size);
write_InvertedLists (ivsc->invlists, f);
} else if(const IndexIVFPQ * ivpq =
dynamic_cast<const IndexIVFPQ *> (idx)) {
const IndexIVFPQR * ivfpqr = dynamic_cast<const IndexIVFPQR *> (idx);
uint32_t h = fourcc (ivfpqr ? "IwQR" : "IwPQ");
WRITE1 (h);
write_ivf_header (ivpq, f);
WRITE1 (ivpq->by_residual);
WRITE1 (ivpq->code_size);
write_ProductQuantizer (&ivpq->pq, f);
write_InvertedLists (ivpq->invlists, f);
if (ivfpqr) {
write_ProductQuantizer (&ivfpqr->refine_pq, f);
WRITEVECTOR (ivfpqr->refine_codes);
WRITE1 (ivfpqr->k_factor);
}
} else if(const IndexPreTransform * ixpt =
dynamic_cast<const IndexPreTransform *> (idx)) {
uint32_t h = fourcc ("IxPT");
WRITE1 (h);
write_index_header (ixpt, f);
int nt = ixpt->chain.size();
WRITE1 (nt);
for (int i = 0; i < nt; i++)
write_VectorTransform (ixpt->chain[i], f);
write_index (ixpt->index, f);
} else if(const MultiIndexQuantizer * imiq =
dynamic_cast<const MultiIndexQuantizer *> (idx)) {
uint32_t h = fourcc ("Imiq");
WRITE1 (h);
write_index_header (imiq, f);
write_ProductQuantizer (&imiq->pq, f);
} else if(const IndexRefineFlat * idxrf =
dynamic_cast<const IndexRefineFlat *> (idx)) {
uint32_t h = fourcc ("IxRF");
WRITE1 (h);
write_index_header (idxrf, f);
write_index (idxrf->base_index, f);
write_index (&idxrf->refine_index, f);
WRITE1 (idxrf->k_factor);
} else if(const IndexIDMap * idxmap =
dynamic_cast<const IndexIDMap *> (idx)) {
uint32_t h =
dynamic_cast<const IndexIDMap2 *> (idx) ? fourcc ("IxM2") :
fourcc ("IxMp");
// no need to store additional info for IndexIDMap2
WRITE1 (h);
write_index_header (idxmap, f);
write_index (idxmap->index, f);
WRITEVECTOR (idxmap->id_map);
} else if(const IndexHNSW * idxhnsw =
dynamic_cast<const IndexHNSW *> (idx)) {
uint32_t h =
dynamic_cast<const IndexHNSWFlat*>(idx) ? fourcc("IHNf") :
dynamic_cast<const IndexHNSWPQ*>(idx) ? fourcc("IHNp") :
dynamic_cast<const IndexHNSWSQ*>(idx) ? fourcc("IHNs") :
dynamic_cast<const IndexHNSW2Level*>(idx) ? fourcc("IHN2") :
0;
FAISS_THROW_IF_NOT (h != 0);
WRITE1 (h);
write_index_header (idxhnsw, f);
write_HNSW (&idxhnsw->hnsw, f);
write_index (idxhnsw->storage, f);
} else {
FAISS_THROW_MSG ("don't know how to serialize this type of index");
}
}
void write_index (const Index *idx, FILE *f) {
FileIOWriter writer(f);
write_index (idx, &writer);
}
void write_index (const Index *idx, const char *fname) {
FileIOWriter writer(fname);
write_index (idx, &writer);
}
void write_VectorTransform (const VectorTransform *vt, const char *fname) {
FileIOWriter writer(fname);
write_VectorTransform (vt, &writer);
}
/*************************************************************
* Read
**************************************************************/
static void read_index_header (Index *idx, IOReader *f) {
READ1 (idx->d);
READ1 (idx->ntotal);
Index::idx_t dummy;
READ1 (dummy);
READ1 (dummy);
READ1 (idx->is_trained);
READ1 (idx->metric_type);
idx->verbose = false;
}
VectorTransform* read_VectorTransform (IOReader *f) {
uint32_t h;
READ1 (h);
VectorTransform *vt = nullptr;
if (h == fourcc ("rrot") || h == fourcc ("PCAm") ||
h == fourcc ("LTra") || h == fourcc ("PcAm")) {
LinearTransform *lt = nullptr;
if (h == fourcc ("rrot")) {
lt = new RandomRotationMatrix ();
} else if (h == fourcc ("PCAm") ||
h == fourcc ("PcAm")) {
PCAMatrix * pca = new PCAMatrix ();
READ1 (pca->eigen_power);
READ1 (pca->random_rotation);
if (h == fourcc ("PcAm"))
READ1 (pca->balanced_bins);
READVECTOR (pca->mean);
READVECTOR (pca->eigenvalues);
READVECTOR (pca->PCAMat);
lt = pca;
} else if (h == fourcc ("LTra")) {
lt = new LinearTransform ();
}
READ1 (lt->have_bias);
READVECTOR (lt->A);
READVECTOR (lt->b);
FAISS_THROW_IF_NOT (lt->A.size() >= lt->d_in * lt->d_out);
FAISS_THROW_IF_NOT (!lt->have_bias || lt->b.size() >= lt->d_out);
lt->set_is_orthonormal();
vt = lt;
} else if (h == fourcc ("RmDT")) {
RemapDimensionsTransform *rdt = new RemapDimensionsTransform ();
READVECTOR (rdt->map);
vt = rdt;
} else if (h == fourcc ("VNrm")) {
NormalizationTransform *nt = new NormalizationTransform ();
READ1 (nt->norm);
vt = nt;
} else {
FAISS_THROW_MSG("fourcc not recognized");
}
READ1 (vt->d_in);
READ1 (vt->d_out);
READ1 (vt->is_trained);
return vt;
}
static void read_ArrayInvertedLists_sizes (
IOReader *f, std::vector<size_t> & sizes)
{
uint32_t list_type;
READ1(list_type);
if (list_type == fourcc("full")) {
size_t os = sizes.size();
READVECTOR (sizes);
FAISS_THROW_IF_NOT (os == sizes.size());
} else if (list_type == fourcc("sprs")) {
std::vector<size_t> idsizes;
READVECTOR (idsizes);
for (size_t j = 0; j < idsizes.size(); j += 2) {
FAISS_THROW_IF_NOT (idsizes[j] < sizes.size());
sizes[idsizes[j]] = idsizes[j + 1];
}
} else {
FAISS_THROW_MSG ("invalid list_type");
}
}
InvertedLists *read_InvertedLists (IOReader *f, int io_flags) {
uint32_t h;
READ1 (h);
if (h == fourcc ("il00")) {
fprintf(stderr, "read_InvertedLists:"
" WARN! inverted lists not stored with IVF object\n");
return nullptr;
} else if (h == fourcc ("ilar") && !(io_flags & IO_FLAG_MMAP)) {
auto ails = new ArrayInvertedLists (0, 0);
READ1 (ails->nlist);
READ1 (ails->code_size);
ails->ids.resize (ails->nlist);
ails->codes.resize (ails->nlist);
std::vector<size_t> sizes (ails->nlist);
read_ArrayInvertedLists_sizes (f, sizes);
for (size_t i = 0; i < ails->nlist; i++) {
ails->ids[i].resize (sizes[i]);
ails->codes[i].resize (sizes[i] * ails->code_size);
}
for (size_t i = 0; i < ails->nlist; i++) {
size_t n = ails->ids[i].size();
if (n > 0) {
READANDCHECK (ails->codes[i].data(), n * ails->code_size);
READANDCHECK (ails->ids[i].data(), n);
}
}
return ails;
} else if (h == fourcc ("ilar") && (io_flags & IO_FLAG_MMAP)) {
// then we load it as an OnDiskInvertedLists
FileIOReader *reader = dynamic_cast<FileIOReader*>(f);
FAISS_THROW_IF_NOT_MSG(reader, "mmap only supported for File objects");
FILE *fdesc = reader->f;
auto ails = new OnDiskInvertedLists ();
READ1 (ails->nlist);
READ1 (ails->code_size);
ails->read_only = true;
ails->lists.resize (ails->nlist);
std::vector<size_t> sizes (ails->nlist);
read_ArrayInvertedLists_sizes (f, sizes);
size_t o0 = ftell(fdesc), o = o0;
{ // do the mmap
struct stat buf;
int ret = fstat (fileno(fdesc), &buf);
FAISS_THROW_IF_NOT_FMT (ret == 0,
"fstat failed: %s", strerror(errno));
ails->totsize = buf.st_size;
ails->ptr = (uint8_t*)mmap (nullptr, ails->totsize,
PROT_READ, MAP_SHARED,
fileno(fdesc), 0);
FAISS_THROW_IF_NOT_FMT (ails->ptr != MAP_FAILED,
"could not mmap: %s",
strerror(errno));
}
for (size_t i = 0; i < ails->nlist; i++) {
OnDiskInvertedLists::List & l = ails->lists[i];
l.size = l.capacity = sizes[i];
l.offset = o;
o += l.size * (sizeof(OnDiskInvertedLists::idx_t) +
ails->code_size);
}
FAISS_THROW_IF_NOT(o <= ails->totsize);
// resume normal reading of file
fseek (fdesc, o, SEEK_SET);
return ails;
} else if (h == fourcc ("ilod")) {
OnDiskInvertedLists *od = new OnDiskInvertedLists();
od->read_only = io_flags & IO_FLAG_READ_ONLY;
READ1 (od->nlist);
READ1 (od->code_size);
// this is a POD object
READVECTOR (od->lists);
{
std::vector<OnDiskInvertedLists::Slot> v;
READVECTOR(v);
od->slots.assign(v.begin(), v.end());
}
{
std::vector<char> x;
READVECTOR(x);
od->filename.assign(x.begin(), x.end());
}
READ1(od->totsize);
od->do_mmap();
return od;
} else {
FAISS_THROW_MSG ("read_InvertedLists: unsupported invlist type");
}
}
static void read_InvertedLists (
IndexIVF *ivf, IOReader *f, int io_flags) {
InvertedLists *ils = read_InvertedLists (f, io_flags);
FAISS_THROW_IF_NOT (!ils || (ils->nlist == ivf->nlist &&
ils->code_size == ivf->code_size));
ivf->invlists = ils;
ivf->own_invlists = true;
}
static void read_InvertedLists (
IndexBinaryIVF *ivf, IOReader *f, int io_flags) {
InvertedLists *ils = read_InvertedLists (f, io_flags);
FAISS_THROW_IF_NOT (!ils || (ils->nlist == ivf->nlist &&
ils->code_size == ivf->code_size));
ivf->invlists = ils;
ivf->own_invlists = true;
}
static void read_ProductQuantizer (ProductQuantizer *pq, IOReader *f) {
READ1 (pq->d);
READ1 (pq->M);
READ1 (pq->nbits);
pq->set_derived_values ();
READVECTOR (pq->centroids);
}
static void read_ScalarQuantizer (ScalarQuantizer *ivsc, IOReader *f) {
READ1 (ivsc->qtype);
READ1 (ivsc->rangestat);
READ1 (ivsc->rangestat_arg);
READ1 (ivsc->d);
READ1 (ivsc->code_size);
READVECTOR (ivsc->trained);
}
static void read_HNSW (HNSW *hnsw, IOReader *f) {
READVECTOR (hnsw->assign_probas);
READVECTOR (hnsw->cum_nneighbor_per_level);
READVECTOR (hnsw->levels);
READVECTOR (hnsw->offsets);
READVECTOR (hnsw->neighbors);
READ1 (hnsw->entry_point);
READ1 (hnsw->max_level);
READ1 (hnsw->efConstruction);
READ1 (hnsw->efSearch);
READ1 (hnsw->upper_beam);
}
ProductQuantizer * read_ProductQuantizer (const char*fname) {
FileIOReader reader(fname);
return read_ProductQuantizer(&reader);
}
ProductQuantizer * read_ProductQuantizer (IOReader *reader) {
ProductQuantizer *pq = new ProductQuantizer();
ScopeDeleter1<ProductQuantizer> del (pq);
read_ProductQuantizer(pq, reader);
del.release ();
return pq;
}
static void read_ivf_header (
IndexIVF *ivf, IOReader *f,
std::vector<std::vector<Index::idx_t> > *ids = nullptr)
{
read_index_header (ivf, f);
READ1 (ivf->nlist);
READ1 (ivf->nprobe);
ivf->quantizer = read_index (f);
ivf->own_fields = true;
if (ids) { // used in legacy "Iv" formats
ids->resize (ivf->nlist);
for (size_t i = 0; i < ivf->nlist; i++)
READVECTOR ((*ids)[i]);
}
READ1 (ivf->maintain_direct_map);
READVECTOR (ivf->direct_map);
}
// used for legacy formats
static ArrayInvertedLists *set_array_invlist(
IndexIVF *ivf, std::vector<std::vector<Index::idx_t> > &ids)
{
ArrayInvertedLists *ail = new ArrayInvertedLists (
ivf->nlist, ivf->code_size);
std::swap (ail->ids, ids);
ivf->invlists = ail;
ivf->own_invlists = true;
return ail;
}
static IndexIVFPQ *read_ivfpq (IOReader *f, uint32_t h, int io_flags)
{
bool legacy = h == fourcc ("IvQR") || h == fourcc ("IvPQ");
IndexIVFPQR *ivfpqr =
h == fourcc ("IvQR") || h == fourcc ("IwQR") ?
new IndexIVFPQR () : nullptr;
IndexIVFPQ * ivpq = ivfpqr ? ivfpqr : new IndexIVFPQ ();
std::vector<std::vector<Index::idx_t> > ids;
read_ivf_header (ivpq, f, legacy ? &ids : nullptr);
READ1 (ivpq->by_residual);
READ1 (ivpq->code_size);
read_ProductQuantizer (&ivpq->pq, f);
if (legacy) {
ArrayInvertedLists *ail = set_array_invlist (ivpq, ids);
for (size_t i = 0; i < ail->nlist; i++)
READVECTOR (ail->codes[i]);
} else {
read_InvertedLists (ivpq, f, io_flags);
}
// precomputed table not stored. It is cheaper to recompute it
ivpq->use_precomputed_table = 0;
if (ivpq->by_residual)
ivpq->precompute_table ();
if (ivfpqr) {
read_ProductQuantizer (&ivfpqr->refine_pq, f);
READVECTOR (ivfpqr->refine_codes);
READ1 (ivfpqr->k_factor);
}
return ivpq;
}
int read_old_fmt_hack = 0;
Index *read_index (IOReader *f, int io_flags) {
Index * idx = nullptr;
uint32_t h;
READ1 (h);
if (h == fourcc ("IxFI") || h == fourcc ("IxF2")) {
IndexFlat *idxf;
if (h == fourcc ("IxFI")) idxf = new IndexFlatIP ();
else idxf = new IndexFlatL2 ();
read_index_header (idxf, f);
READVECTOR (idxf->xb);
FAISS_THROW_IF_NOT (idxf->xb.size() == idxf->ntotal * idxf->d);
// leak!
idx = idxf;
} else if (h == fourcc("IxHE") || h == fourcc("IxHe")) {
IndexLSH * idxl = new IndexLSH ();
read_index_header (idxl, f);
READ1 (idxl->nbits);
READ1 (idxl->rotate_data);
READ1 (idxl->train_thresholds);
READVECTOR (idxl->thresholds);
READ1 (idxl->bytes_per_vec);
if (h == fourcc("IxHE")) {
FAISS_THROW_IF_NOT_FMT (idxl->nbits % 64 == 0,
"can only read old format IndexLSH with "
"nbits multiple of 64 (got %d)",
(int) idxl->nbits);
// leak
idxl->bytes_per_vec *= 8;
}
{
RandomRotationMatrix *rrot = dynamic_cast<RandomRotationMatrix *>
(read_VectorTransform (f));
FAISS_THROW_IF_NOT_MSG(rrot, "expected a random rotation");
idxl->rrot = *rrot;
delete rrot;
}
READVECTOR (idxl->codes);
FAISS_THROW_IF_NOT (idxl->rrot.d_in == idxl->d &&
idxl->rrot.d_out == idxl->nbits);
FAISS_THROW_IF_NOT (
idxl->codes.size() == idxl->ntotal * idxl->bytes_per_vec);
idx = idxl;
} else if (h == fourcc ("IxPQ") || h == fourcc ("IxPo") ||
h == fourcc ("IxPq")) {
// IxPQ and IxPo were merged into the same IndexPQ object
IndexPQ * idxp =new IndexPQ ();
read_index_header (idxp, f);
read_ProductQuantizer (&idxp->pq, f);
READVECTOR (idxp->codes);
if (h == fourcc ("IxPo") || h == fourcc ("IxPq")) {
READ1 (idxp->search_type);
READ1 (idxp->encode_signs);
READ1 (idxp->polysemous_ht);
}
// Old versoins of PQ all had metric_type set to INNER_PRODUCT
// when they were in fact using L2. Therefore, we force metric type
// to L2 when the old format is detected
if (h == fourcc ("IxPQ") || h == fourcc ("IxPo")) {
idxp->metric_type = METRIC_L2;
}
idx = idxp;
} else if (h == fourcc ("IvFl") || h == fourcc("IvFL")) { // legacy
IndexIVFFlat * ivfl = new IndexIVFFlat ();
std::vector<std::vector<Index::idx_t> > ids;
read_ivf_header (ivfl, f, &ids);
ivfl->code_size = ivfl->d * sizeof(float);
ArrayInvertedLists *ail = set_array_invlist (ivfl, ids);
if (h == fourcc ("IvFL")) {
for (size_t i = 0; i < ivfl->nlist; i++) {
READVECTOR (ail->codes[i]);
}
} else { // old format
for (size_t i = 0; i < ivfl->nlist; i++) {
std::vector<float> vec;
READVECTOR (vec);
ail->codes[i].resize(vec.size() * sizeof(float));
memcpy(ail->codes[i].data(), vec.data(),
ail->codes[i].size());
}
}
idx = ivfl;
} else if (h == fourcc ("IwFd")) {
IndexIVFFlatDedup * ivfl = new IndexIVFFlatDedup ();
read_ivf_header (ivfl, f);
ivfl->code_size = ivfl->d * sizeof(float);
{
std::vector<Index::idx_t> tab;
READVECTOR (tab);
for (long i = 0; i < tab.size(); i += 2) {
std::pair<Index::idx_t, Index::idx_t>
pair (tab[i], tab[i + 1]);
ivfl->instances.insert (pair);
}
}
read_InvertedLists (ivfl, f, io_flags);
idx = ivfl;
} else if (h == fourcc ("IwFl")) {
IndexIVFFlat * ivfl = new IndexIVFFlat ();
read_ivf_header (ivfl, f);
ivfl->code_size = ivfl->d * sizeof(float);
read_InvertedLists (ivfl, f, io_flags);
idx = ivfl;
} else if (h == fourcc ("IxSQ")) {
IndexScalarQuantizer * idxs = new IndexScalarQuantizer ();
read_index_header (idxs, f);
read_ScalarQuantizer (&idxs->sq, f);
READVECTOR (idxs->codes);
idxs->code_size = idxs->sq.code_size;
idx = idxs;
} else if(h == fourcc ("IvSQ")) { // legacy
IndexIVFScalarQuantizer * ivsc = new IndexIVFScalarQuantizer();
std::vector<std::vector<Index::idx_t> > ids;
read_ivf_header (ivsc, f, &ids);
read_ScalarQuantizer (&ivsc->sq, f);
READ1 (ivsc->code_size);
ArrayInvertedLists *ail = set_array_invlist (ivsc, ids);
for(int i = 0; i < ivsc->nlist; i++)
READVECTOR (ail->codes[i]);
idx = ivsc;
} else if(h == fourcc ("IwSQ")) {
IndexIVFScalarQuantizer * ivsc = new IndexIVFScalarQuantizer();
read_ivf_header (ivsc, f);
read_ScalarQuantizer (&ivsc->sq, f);
READ1 (ivsc->code_size);
read_InvertedLists (ivsc, f, io_flags);
idx = ivsc;
} else if(h == fourcc ("IvPQ") || h == fourcc ("IvQR") ||
h == fourcc ("IwPQ") || h == fourcc ("IwQR")) {
idx = read_ivfpq (f, h, io_flags);
} else if(h == fourcc ("IxPT")) {
IndexPreTransform * ixpt = new IndexPreTransform();
ixpt->own_fields = true;
read_index_header (ixpt, f);
int nt;
if (read_old_fmt_hack == 2) {
nt = 1;
} else {
READ1 (nt);
}
for (int i = 0; i < nt; i++) {
ixpt->chain.push_back (read_VectorTransform (f));
}
ixpt->index = read_index (f, io_flags);
idx = ixpt;
} else if(h == fourcc ("Imiq")) {
MultiIndexQuantizer * imiq = new MultiIndexQuantizer ();
read_index_header (imiq, f);
read_ProductQuantizer (&imiq->pq, f);
idx = imiq;
} else if(h == fourcc ("IxRF")) {
IndexRefineFlat *idxrf = new IndexRefineFlat ();
read_index_header (idxrf, f);
idxrf->base_index = read_index(f, io_flags);
idxrf->own_fields = true;
IndexFlat *rf = dynamic_cast<IndexFlat*> (read_index (f, io_flags));
std::swap (*rf, idxrf->refine_index);
delete rf;
READ1 (idxrf->k_factor);
idx = idxrf;
} else if(h == fourcc ("IxMp") || h == fourcc ("IxM2")) {
bool is_map2 = h == fourcc ("IxM2");
IndexIDMap * idxmap = is_map2 ? new IndexIDMap2 () : new IndexIDMap ();
read_index_header (idxmap, f);
idxmap->index = read_index (f, io_flags);
idxmap->own_fields = true;
READVECTOR (idxmap->id_map);
if (is_map2) {
static_cast<IndexIDMap2*>(idxmap)->construct_rev_map ();
}
idx = idxmap;
} else if (h == fourcc ("Ix2L")) {
Index2Layer * idxp = new Index2Layer ();
read_index_header (idxp, f);
idxp->q1.quantizer = read_index (f, io_flags);
READ1 (idxp->q1.nlist);
READ1 (idxp->q1.quantizer_trains_alone);
read_ProductQuantizer (&idxp->pq, f);
READ1 (idxp->code_size_1);
READ1 (idxp->code_size_2);
READ1 (idxp->code_size);
READVECTOR (idxp->codes);
idx = idxp;
} else if(h == fourcc("IHNf") || h == fourcc("IHNp") ||
h == fourcc("IHNs") || h == fourcc("IHN2")) {
IndexHNSW *idxhnsw = nullptr;
if (h == fourcc("IHNf")) idxhnsw = new IndexHNSWFlat ();
if (h == fourcc("IHNp")) idxhnsw = new IndexHNSWPQ ();
if (h == fourcc("IHNs")) idxhnsw = new IndexHNSWSQ ();
if (h == fourcc("IHN2")) idxhnsw = new IndexHNSW2Level ();
read_index_header (idxhnsw, f);
read_HNSW (&idxhnsw->hnsw, f);
idxhnsw->storage = read_index (f, io_flags);
idxhnsw->own_fields = true;
if (h == fourcc("IHNp")) {
dynamic_cast<IndexPQ*>(idxhnsw->storage)->pq.compute_sdc_table ();
}
idx = idxhnsw;
} else {
FAISS_THROW_FMT("Index type 0x%08x not supported\n", h);
idx = nullptr;
}
return idx;
}
Index *read_index (FILE * f, int io_flags) {
FileIOReader reader(f);
return read_index(&reader, io_flags);
}
Index *read_index (const char *fname, int io_flags) {
FileIOReader reader(fname);
Index *idx = read_index (&reader, io_flags);
return idx;
}
VectorTransform *read_VectorTransform (const char *fname) {
FileIOReader reader(fname);
VectorTransform *vt = read_VectorTransform (&reader);
return vt;
}
/*************************************************************
* cloning functions
**************************************************************/
Index * clone_index (const Index *index)
{
Cloner cl;
return cl.clone_Index (index);
}
// assumes there is a copy constructor ready. Always try from most
// specific to most general
#define TRYCLONE(classname, obj) \
if (const classname *clo = dynamic_cast<const classname *>(obj)) { \
return new classname(*clo); \
} else
VectorTransform *Cloner::clone_VectorTransform (const VectorTransform *vt)
{
TRYCLONE (RemapDimensionsTransform, vt)
TRYCLONE (OPQMatrix, vt)
TRYCLONE (PCAMatrix, vt)
TRYCLONE (RandomRotationMatrix, vt)
TRYCLONE (LinearTransform, vt)
{
FAISS_THROW_MSG("clone not supported for this type of VectorTransform");
}
return nullptr;
}
IndexIVF * Cloner::clone_IndexIVF (const IndexIVF *ivf)
{
TRYCLONE (IndexIVFPQR, ivf)
TRYCLONE (IndexIVFPQ, ivf)
TRYCLONE (IndexIVFFlat, ivf)
TRYCLONE (IndexIVFScalarQuantizer, ivf)
{
FAISS_THROW_MSG("clone not supported for this type of IndexIVF");
}
return nullptr;
}
Index *Cloner::clone_Index (const Index *index)
{
TRYCLONE (IndexPQ, index)
TRYCLONE (IndexLSH, index)
TRYCLONE (IndexFlatL2, index)
TRYCLONE (IndexFlatIP, index)
TRYCLONE (IndexFlat, index)
TRYCLONE (IndexScalarQuantizer, index)
TRYCLONE (MultiIndexQuantizer, index)
if (const IndexIVF * ivf = dynamic_cast<const IndexIVF*>(index)) {
IndexIVF *res = clone_IndexIVF (ivf);
if (ivf->invlists == nullptr) {
res->invlists = nullptr;
} else if (auto *ails = dynamic_cast<const ArrayInvertedLists*>
(ivf->invlists)) {
res->invlists = new ArrayInvertedLists(*ails);
res->own_invlists = true;
} else {
FAISS_THROW_MSG( "clone not supported for this type of inverted lists");
}
res->own_fields = true;
res->quantizer = clone_Index (ivf->quantizer);
return res;
} else if (const IndexPreTransform * ipt =
dynamic_cast<const IndexPreTransform*> (index)) {
IndexPreTransform *res = new IndexPreTransform ();
res->d = ipt->d;
res->index = clone_Index (ipt->index);
for (int i = 0; i < ipt->chain.size(); i++)
res->chain.push_back (clone_VectorTransform (ipt->chain[i]));
res->own_fields = true;
return res;
} else if (const IndexIDMap *idmap =
dynamic_cast<const IndexIDMap*> (index)) {
IndexIDMap *res = new IndexIDMap (*idmap);
res->own_fields = true;
res->index = clone_Index (idmap->index);
return res;
} else {
FAISS_THROW_MSG( "clone not supported for this type of Index");
}
return nullptr;
}
static void write_index_binary_header (const IndexBinary *idx, IOWriter *f) {
WRITE1 (idx->d);
WRITE1 (idx->code_size);
WRITE1 (idx->ntotal);
WRITE1 (idx->is_trained);
WRITE1 (idx->metric_type);
}
static void write_binary_ivf_header (const IndexBinaryIVF *ivf, IOWriter *f) {
write_index_binary_header (ivf, f);
WRITE1 (ivf->nlist);
WRITE1 (ivf->nprobe);
write_index_binary (ivf->quantizer, f);
WRITE1 (ivf->maintain_direct_map);
WRITEVECTOR (ivf->direct_map);
}
void write_index_binary (const IndexBinary *idx, IOWriter *f) {
if (const IndexBinaryFlat *idxf =
dynamic_cast<const IndexBinaryFlat *> (idx)) {
uint32_t h = fourcc ("IBxF");
WRITE1 (h);
write_index_binary_header (idx, f);
WRITEVECTOR (idxf->xb);
} else if (const IndexBinaryIVF *ivf =
dynamic_cast<const IndexBinaryIVF *> (idx)) {
uint32_t h = fourcc ("IBwF");
WRITE1 (h);
write_binary_ivf_header (ivf, f);
write_InvertedLists (ivf->invlists, f);
} else if(const IndexBinaryFromFloat * idxff =
dynamic_cast<const IndexBinaryFromFloat *> (idx)) {
uint32_t h = fourcc ("IBFf");
WRITE1 (h);
write_index_binary_header (idxff, f);
write_index (idxff->index, f);
} else if (const IndexBinaryHNSW *idxhnsw =
dynamic_cast<const IndexBinaryHNSW *> (idx)) {
uint32_t h = fourcc ("IBHf");
WRITE1 (h);
write_index_binary_header (idxhnsw, f);
write_HNSW (&idxhnsw->hnsw, f);
write_index_binary (idxhnsw->storage, f);
} else {
FAISS_THROW_MSG ("don't know how to serialize this type of index");
}
}
void write_index_binary (const IndexBinary *idx, FILE *f) {
FileIOWriter writer(f);
write_index_binary(idx, &writer);
}
void write_index_binary (const IndexBinary *idx, const char *fname) {
FileIOWriter writer(fname);
write_index_binary (idx, &writer);
}
static void read_index_binary_header (IndexBinary *idx, IOReader *f) {
READ1 (idx->d);
READ1 (idx->code_size);
READ1 (idx->ntotal);
READ1 (idx->is_trained);
READ1 (idx->metric_type);
idx->verbose = false;
}
static void read_binary_ivf_header (
IndexBinaryIVF *ivf, IOReader *f,
std::vector<std::vector<Index::idx_t> > *ids = nullptr)
{
read_index_binary_header (ivf, f);
READ1 (ivf->nlist);
READ1 (ivf->nprobe);
ivf->quantizer = read_index_binary (f);
ivf->own_fields = true;
if (ids) { // used in legacy "Iv" formats
ids->resize (ivf->nlist);
for (size_t i = 0; i < ivf->nlist; i++)
READVECTOR ((*ids)[i]);
}
READ1 (ivf->maintain_direct_map);
READVECTOR (ivf->direct_map);
}
IndexBinary *read_index_binary (IOReader *f, int io_flags) {
IndexBinary * idx = nullptr;
uint32_t h;
READ1 (h);
if (h == fourcc ("IBxF")) {
IndexBinaryFlat *idxf = new IndexBinaryFlat ();
read_index_binary_header (idxf, f);
READVECTOR (idxf->xb);
FAISS_THROW_IF_NOT (idxf->xb.size() == idxf->ntotal * idxf->code_size);
// leak!
idx = idxf;
} else if (h == fourcc ("IBwF")) {
IndexBinaryIVF *ivf = new IndexBinaryIVF ();
read_binary_ivf_header (ivf, f);
read_InvertedLists (ivf, f, io_flags);
idx = ivf;
} else if (h == fourcc ("IBFf")) {
IndexBinaryFromFloat *idxff = new IndexBinaryFromFloat ();
read_index_binary_header (idxff, f);
idxff->own_fields = true;
idxff->index = read_index (f, io_flags);
idx = idxff;
} else if (h == fourcc ("IBHf")) {
IndexBinaryHNSW *idxhnsw = new IndexBinaryHNSW ();
read_index_binary_header (idxhnsw, f);
read_HNSW (&idxhnsw->hnsw, f);
idxhnsw->storage = read_index_binary (f, io_flags);
idxhnsw->own_fields = true;
idx = idxhnsw;
} else {
FAISS_THROW_FMT("Index type 0x%08x not supported\n", h);
idx = nullptr;
}
return idx;
}
IndexBinary *read_index_binary (FILE * f, int io_flags) {
FileIOReader reader(f);
return read_index_binary(&reader, io_flags);
}
IndexBinary *read_index_binary (const char *fname, int io_flags) {
FileIOReader reader(fname);
IndexBinary *idx = read_index_binary (&reader, io_flags);
return idx;
}
} // namespace faiss