File IndexShards.h

namespace faiss

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.

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.

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. 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.

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

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. 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.

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

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

Typedefs

using IndexShards = IndexShardsTemplate<Index>
using IndexBinaryShards = IndexShardsTemplate<IndexBinary>
template<typename IndexT>
struct IndexShardsTemplate : public ThreadedIndex<IndexT>
#include <IndexShards.h>

Index that concatenates the results from several sub-indexes

Public Types

using idx_t = typename IndexT::idx_t
using component_t = typename IndexT::component_t
using distance_t = typename IndexT::distance_t

Public Functions

explicit IndexShardsTemplate(bool threaded = false, bool successive_ids = true)

The dimension that all sub-indices must share will be the dimension of the first sub-index added

Parameters
  • threaded – do we use one thread per sub_index or do queries sequentially?

  • successive_ids – should we shift the returned ids by the size of each sub-index or return them as they are?

explicit IndexShardsTemplate(idx_t d, bool threaded = false, bool successive_ids = true)
Parameters
  • threaded – do we use one thread per sub_index or do queries sequentially?

  • successive_ids – should we shift the returned ids by the size of each sub-index or return them as they are?

explicit IndexShardsTemplate(int d, bool threaded = false, bool successive_ids = true)

int version due to the implicit bool conversion ambiguity of int as dimension

inline void add_shard(IndexT *index)

Alias for addIndex()

inline void remove_shard(IndexT *index)

Alias for removeIndex()

void add(idx_t n, const component_t *x) override

supported only for sub-indices that implement add_with_ids

void add_with_ids(idx_t n, const component_t *x, const idx_t *xids) override

Cases (successive_ids, xids):

  • true, non-NULL ERROR: it makes no sense to pass in ids and request them to be shifted

  • true, NULL OK, but should be called only once (calls add() on sub-indexes).

  • false, non-NULL OK: will call add_with_ids with passed in xids distributed evenly over shards

  • false, NULL OK: will call add_with_ids on each sub-index, starting at ntotal

void search(idx_t n, const component_t *x, idx_t k, distance_t *distances, idx_t *labels) const override
void train(idx_t n, const component_t *x) override
void syncWithSubIndexes()

Synchronize the top-level index (IndexShards) with data in the sub-indices

Public Members

bool successive_ids

Protected Functions

void onAfterAddIndex(IndexT *index) override

Called just after an index is added.

void onAfterRemoveIndex(IndexT *index) override

Called just after an index is removed.