Struct faiss::ArrayInvertedLists

struct ArrayInvertedLists : public faiss::InvertedLists

simple (default) implementation as an array of inverted lists

Public Types

enum subset_type_t

Values:

enumerator SUBSET_TYPE_ID_RANGE

enumerator SUBSET_TYPE_ID_MOD

enumerator SUBSET_TYPE_ELEMENT_RANGE

enumerator SUBSET_TYPE_INVLIST_FRACTION

enumerator SUBSET_TYPE_INVLIST

Public Functions

ArrayInvertedLists(size_t nlist, size_t code_size)

virtual size_t list_size(size_t list_no) const override: get the size of a list

virtual const uint8_t *get_codes(size_t list_no) const override

get the codes for an inverted list must be released by release_codes

Returns:: codes size list_size * code_size

virtual const idx_t *get_ids(size_t list_no) const override

get the ids for an inverted list must be released by release_ids

Returns:: ids size list_size

virtual size_t add_entries(size_t list_no, size_t n_entry, const idx_t *ids, const uint8_t *code) override

virtual void update_entries(size_t list_no, size_t offset, size_t n_entry, const idx_t *ids, const uint8_t *code) override

virtual void resize(size_t list_no, size_t new_size) override

void permute_invlists(const idx_t *map): permute the inverted lists, map maps new_id to old_id

virtual bool is_empty(size_t list_no, void *inverted_list_context = nullptr) const override: check if the list is empty

~ArrayInvertedLists() override

virtual void release_codes(size_t list_no, const uint8_t *codes) const: release codes returned by get_codes (default implementation is nop

virtual void release_ids(size_t list_no, const idx_t *ids) const: release ids returned by get_ids

virtual idx_t get_single_id(size_t list_no, size_t offset) const

Returns:: a single id in an inverted list

virtual const uint8_t *get_single_code(size_t list_no, size_t offset) const

Returns:: a single code in an inverted list (should be deallocated with release_codes)

virtual void prefetch_lists(const idx_t *list_nos, int nlist) const: prepare the following lists (default does nothing) a list can be -1 hence the signed long

virtual InvertedListsIterator *get_iterator(size_t list_no, void *inverted_list_context = nullptr) const: get iterable for lists that use_iterator

virtual size_t add_entry(size_t list_no, idx_t theid, const uint8_t *code, void *inverted_list_context = nullptr): add one entry to an inverted list

virtual void update_entry(size_t list_no, size_t offset, idx_t id, const uint8_t *code)

virtual void reset()

void merge_from(InvertedLists *oivf, size_t add_id): move all entries from oivf (empty on output)

size_t copy_subset_to(InvertedLists &other, subset_type_t subset_type, idx_t a1, idx_t a2) const

copy a subset of the entries index to the other index

Returns:: number of entries copied

double imbalance_factor() const: 1= perfectly balanced, >1: imbalanced

void print_stats() const: display some stats about the inverted lists

size_t compute_ntotal() const: sum up list sizes

Public Members

std::vector<std::vector<uint8_t>> codes

std::vector<std::vector<idx_t>> ids: Inverted lists for indexes.

size_t nlist: number of possible key values

size_t code_size: code size per vector in bytes

bool use_iterator = false: request to use iterator rather than get_codes / get_ids

Public Static Attributes

static const size_t INVALID_CODE_SIZE = static_cast<size_t>(-1): used for BlockInvertedLists, where the codes are packed into groups and the individual code size is meaningless