File InvertedListsIOHook.h

namespace faiss

Implementation of k-means clustering with many variants.

Copyright (c) Facebook, Inc. and its affiliates.

This source code is licensed under the MIT license found in the LICENSE file in the root directory of this source tree.

IDSelector is intended to define a subset of vectors to handle (for removal or as subset to search)

PQ4 SIMD packing and accumulation functions

The basic kernel accumulates nq query vectors with bbs = nb * 2 * 16 vectors and produces an output matrix for that. It is interesting for nq * nb <= 4, otherwise register spilling becomes too large.

The implementation of these functions is spread over 3 cpp files to reduce parallel compile times. Templates are instantiated explicitly.

This file contains callbacks for kernels that compute distances.

Throughout the library, vectors are provided as float * pointers. Most algorithms can be optimized when several vectors are processed (added/searched) together in a batch. In this case, they are passed in as a matrix. When n vectors of size d are provided as float * x, component j of vector i is

x[ i * d + j ]

where 0 <= i < n and 0 <= j < d. In other words, matrices are always compact. When specifying the size of the matrix, we call it an n*d matrix, which implies a row-major storage.

I/O functions can read/write to a filename, a file handle or to an object that abstracts the medium.

The read functions return objects that should be deallocated with delete. All references within these objectes are owned by the object.

Definition of inverted lists + a few common classes that implement the interface.

Since IVF (inverted file) indexes are of so much use for large-scale use cases, we group a few functions related to them in this small library. Most functions work both on IndexIVFs and IndexIVFs embedded within an IndexPreTransform.

In this file are the implementations of extra metrics beyond L2 and inner product

Implements a few neural net layers, mainly to support QINCo

Defines a few objects that apply transformations to a set of vectors Often these are pre-processing steps.

struct InvertedListsIOHook
#include <InvertedListsIOHook.h>

Callbacks to handle other types of InvertedList objects.

The callbacks should be registered with add_callback before calling read_index or read_InvertedLists. The callbacks for OnDiskInvertedLists are registrered by default. The invlist type is identified by:

  • the key (a fourcc) at read time

  • the class name (as given by typeid.name) at write time

Subclassed by faiss::BlockInvertedListsIOHook, faiss::OnDiskInvertedListsIOHook

Public Functions

InvertedListsIOHook(const std::string &key, const std::string &classname)
virtual void write(const InvertedLists *ils, IOWriter *f) const = 0

write the index to the IOWriter (including the fourcc)

virtual InvertedLists *read(IOReader *f, int io_flags) const = 0

called when the fourcc matches this class’s fourcc

virtual InvertedLists *read_ArrayInvertedLists(IOReader *f, int io_flags, size_t nlist, size_t code_size, const std::vector<size_t> &sizes) const

read from a ArrayInvertedLists into this invertedlist type. For this to work, the callback has to be enabled and the io_flag has to be set to IO_FLAG_SKIP_IVF_DATA | (16 upper bits of the fourcc)

(default implementation fails)

inline virtual ~InvertedListsIOHook()

Public Members

const std::string key

string version of the fourcc

const std::string classname

typeid.name

Public Static Functions

static void add_callback(InvertedListsIOHook*)
static void print_callbacks()
static InvertedListsIOHook *lookup(int h)
static InvertedListsIOHook *lookup_classname(const std::string &classname)