faiss/gpu/GpuIndexIVFFlat.h

97 lines
2.7 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.
*/
// Copyright 2004-present Facebook. All Rights Reserved.
#pragma once
#include "GpuIndexIVF.h"
namespace faiss { struct IndexIVFFlat; }
namespace faiss { namespace gpu {
class IVFFlat;
class GpuIndexFlat;
struct GpuIndexIVFFlatConfig : public GpuIndexIVFConfig {
inline GpuIndexIVFFlatConfig()
: useFloat16IVFStorage(false) {
}
/// Whether or not IVFFlat inverted list storage is in float16;
/// supported on all architectures
bool useFloat16IVFStorage;
};
/// Wrapper around the GPU implementation that looks like
/// faiss::IndexIVFFlat
class GpuIndexIVFFlat : public GpuIndexIVF {
public:
/// Construct from a pre-existing faiss::IndexIVFFlat instance, copying
/// data over to the given GPU, if the input index is trained.
GpuIndexIVFFlat(GpuResources* resources,
const faiss::IndexIVFFlat* index,
GpuIndexIVFFlatConfig config = GpuIndexIVFFlatConfig());
/// Constructs a new instance with an empty flat quantizer; the user
/// provides the number of lists desired.
GpuIndexIVFFlat(GpuResources* resources,
int dims,
int nlist,
faiss::MetricType metric,
GpuIndexIVFFlatConfig config = GpuIndexIVFFlatConfig());
~GpuIndexIVFFlat() override;
/// Reserve GPU memory in our inverted lists for this number of vectors
void reserveMemory(size_t numVecs);
/// Initialize ourselves from the given CPU index; will overwrite
/// all data in ourselves
void copyFrom(const faiss::IndexIVFFlat* index);
/// Copy ourselves to the given CPU index; will overwrite all data
/// in the index instance
void copyTo(faiss::IndexIVFFlat* index) const;
/// After adding vectors, one can call this to reclaim device memory
/// to exactly the amount needed. Returns space reclaimed in bytes
size_t reclaimMemory();
void reset() override;
void train(Index::idx_t n, const float* x) override;
protected:
/// Called from GpuIndex for add/add_with_ids
void addImpl_(
faiss::Index::idx_t n,
const float* x,
const faiss::Index::idx_t* ids) override;
/// Called from GpuIndex for search
void searchImpl_(
faiss::Index::idx_t n,
const float* x,
faiss::Index::idx_t k,
float* distances,
faiss::Index::idx_t* labels) const override;
private:
GpuIndexIVFFlatConfig ivfFlatConfig_;
/// Desired inverted list memory reservation
size_t reserveMemoryVecs_;
/// Instance that we own; contains the inverted list
IVFFlat* index_;
};
} } // namespace