faiss/benchs/link_and_code/bench_link_and_code.py

305 lines
9.1 KiB
Python

# 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.
#!/usr/bin/env python2
import os
import sys
import time
import numpy as np
import re
import faiss
from multiprocessing.dummy import Pool as ThreadPool
import pdb
import argparse
import datasets
from datasets import sanitize
import neighbor_codec
######################################################
# Command-line parsing
######################################################
parser = argparse.ArgumentParser()
def aa(*args, **kwargs):
group.add_argument(*args, **kwargs)
group = parser.add_argument_group('dataset options')
aa('--db', default='deep1M', help='dataset')
aa( '--compute_gt', default=False, action='store_true',
help='compute and store the groundtruth')
group = parser.add_argument_group('index consturction')
aa('--indexkey', default='HNSW32', help='index_factory type')
aa('--efConstruction', default=200, type=int,
help='HNSW construction factor')
aa('--M0', default=-1, type=int, help='size of base level')
aa('--maxtrain', default=256 * 256, type=int,
help='maximum number of training points')
aa('--indexfile', default='', help='file to read or write index from')
aa('--add_bs', default=-1, type=int,
help='add elements index by batches of this size')
aa('--link_singletons', default=False, action='store_true',
help='do a pass to link in the singletons')
group = parser.add_argument_group(
'searching (reconstruct_from_neighbors options)')
aa('--beta_centroids', default='',
help='file with codebook')
aa('--neigh_recons_codes', default='',
help='file with codes for reconstruction')
aa('--beta_ntrain', default=250000, type=int, help='')
aa('--beta_k', default=256, type=int, help='beta codebook size')
aa('--beta_nsq', default=1, type=int, help='number of beta sub-vectors')
aa('--beta_niter', default=10, type=int, help='')
aa('--k_reorder', default='-1', help='')
group = parser.add_argument_group('searching')
aa('--k', default=100, type=int, help='nb of nearest neighbors')
aa('--exhaustive', default=False, action='store_true',
help='report the exhaustive search topline')
aa('--searchthreads', default=-1, type=int,
help='nb of threads to use at search time')
aa('--efSearch', default='', type=str,
help='comma-separated values of efSearch to try')
args = parser.parse_args()
print "args:", args
######################################################
# Load dataset
######################################################
xt, xb, xq, gt = datasets.load_data(
dataset=args.db, compute_gt=args.compute_gt)
nq, d = xq.shape
nb, d = xb.shape
######################################################
# Make index
######################################################
if os.path.exists(args.indexfile):
print "reading", args.indexfile
index = faiss.read_index(args.indexfile)
if isinstance(index, faiss.IndexPreTransform):
index_hnsw = faiss.downcast_index(index.index)
vec_transform = index.chain.at(0).apply_py
else:
index_hnsw = index
vec_transform = lambda x:x
hnsw = index_hnsw.hnsw
hnsw_stats = faiss.cvar.hnsw_stats
else:
print "build index, key=", args.indexkey
index = faiss.index_factory(d, args.indexkey)
if isinstance(index, faiss.IndexPreTransform):
index_hnsw = faiss.downcast_index(index.index)
vec_transform = index.chain.at(0).apply_py
else:
index_hnsw = index
vec_transform = lambda x:x
hnsw = index_hnsw.hnsw
hnsw.efConstruction = args.efConstruction
hnsw_stats = faiss.cvar.hnsw_stats
index.verbose = True
index_hnsw.verbose = True
index_hnsw.storage.verbose = True
if args.M0 != -1:
print "set level 0 nb of neighbors to", args.M0
hnsw.set_nb_neighbors(0, args.M0)
xt2 = sanitize(xt[:args.maxtrain])
assert np.all(np.isfinite(xt2))
print "train, size", xt.shape
t0 = time.time()
index.train(xt2)
print " train in %.3f s" % (time.time() - t0)
print "adding"
t0 = time.time()
if args.add_bs == -1:
index.add(sanitize(xb))
else:
for i0 in range(0, nb, args.add_bs):
i1 = min(nb, i0 + args.add_bs)
print " adding %d:%d / %d" % (i0, i1, nb)
index.add(sanitize(xb[i0:i1]))
print " add in %.3f s" % (time.time() - t0)
print "storing", args.indexfile
faiss.write_index(index, args.indexfile)
######################################################
# Train beta centroids and encode dataset
######################################################
if args.beta_centroids:
print "reordering links"
index_hnsw.reorder_links()
if os.path.exists(args.beta_centroids):
print "load", args.beta_centroids
beta_centroids = np.load(args.beta_centroids)
nsq, k, M1 = beta_centroids.shape
assert M1 == hnsw.nb_neighbors(0) + 1
rfn = faiss.ReconstructFromNeighbors(index_hnsw, k, nsq)
else:
print "train beta centroids"
rfn = faiss.ReconstructFromNeighbors(
index_hnsw, args.beta_k, args.beta_nsq)
xb_full = vec_transform(sanitize(xb[:args.beta_ntrain]))
beta_centroids = neighbor_codec.train_beta_codebook(
rfn, xb_full, niter=args.beta_niter)
print " storing", args.beta_centroids
np.save(args.beta_centroids, beta_centroids)
faiss.copy_array_to_vector(beta_centroids.ravel(),
rfn.codebook)
index_hnsw.reconstruct_from_neighbors = rfn
if rfn.k == 1:
pass # no codes to take care of
elif os.path.exists(args.neigh_recons_codes):
print "loading neigh codes", args.neigh_recons_codes
codes = np.load(args.neigh_recons_codes)
assert codes.size == rfn.code_size * index.ntotal
faiss.copy_array_to_vector(codes.astype('uint8'),
rfn.codes)
rfn.ntotal = index.ntotal
else:
print "encoding neigh codes"
t0 = time.time()
bs = 1000000 if args.add_bs == -1 else args.add_bs
for i0 in range(0, nb, bs):
i1 = min(i0 + bs, nb)
print " encode %d:%d / %d [%.3f s]\r" % (
i0, i1, nb, time.time() - t0),
sys.stdout.flush()
xbatch = vec_transform(sanitize(xb[i0:i1]))
rfn.add_codes(i1 - i0, faiss.swig_ptr(xbatch))
print
print "storing %s" % args.neigh_recons_codes
codes = faiss.vector_to_array(rfn.codes)
np.save(args.neigh_recons_codes, codes)
######################################################
# Exhaustive evaluation
######################################################
if args.exhaustive:
print "exhaustive evaluation"
xq_tr = vec_transform(sanitize(xq))
index2 = faiss.IndexFlatL2(index_hnsw.d)
accu_recons_error = 0.0
if faiss.get_num_gpus() > 0:
print "do eval on GPU"
co = faiss.GpuMultipleClonerOptions()
co.shard = False
index2 = faiss.index_cpu_to_all_gpus(index2, co)
# process in batches in case the dataset does not fit in RAM
rh = datasets.ResultHeap(xq_tr.shape[0], 100)
t0 = time.time()
bs = 500000
for i0 in range(0, nb, bs):
i1 = min(nb, i0 + bs)
print ' handling batch %d:%d' % (i0, i1)
xb_recons = np.empty(
(i1 - i0, index_hnsw.d), dtype='float32')
rfn.reconstruct_n(i0, i1 - i0, faiss.swig_ptr(xb_recons))
accu_recons_error += (
(vec_transform(sanitize(xb[i0:i1])) -
xb_recons)**2).sum()
index2.reset()
index2.add(xb_recons)
D, I = index2.search(xq_tr, 100)
rh.add_batch_result(D, I, i0)
rh.finalize()
del index2
t1 = time.time()
print "done in %.3f s" % (t1 - t0)
print "total reconstruction error: ", accu_recons_error
print "eval retrieval:"
datasets.evaluate_DI(rh.D, rh.I, gt)
def get_neighbors(hnsw, i, level):
" list the neighbors for node i at level "
assert i < hnsw.levels.size()
assert level < hnsw.levels.at(i)
be = np.empty(2, 'uint64')
hnsw.neighbor_range(i, level, faiss.swig_ptr(be), faiss.swig_ptr(be[1:]))
return [hnsw.neighbors.at(j) for j in range(be[0], be[1])]
#############################################################
# Index is ready
#############################################################
xq = sanitize(xq)
if args.searchthreads != -1:
print "Setting nb of threads to", args.searchthreads
faiss.omp_set_num_threads(args.searchthreads)
if gt is None:
print "no valid groundtruth -- exit"
sys.exit()
k_reorders = [int(x) for x in args.k_reorder.split(',')]
efSearchs = [int(x) for x in args.efSearch.split(',')]
for k_reorder in k_reorders:
if index_hnsw.reconstruct_from_neighbors:
print "setting k_reorder=%d" % k_reorder
index_hnsw.reconstruct_from_neighbors.k_reorder = k_reorder
for efSearch in efSearchs:
print "efSearch=%-4d" % efSearch,
hnsw.efSearch = efSearch
hnsw_stats.reset()
datasets.evaluate(xq, gt, index, k=args.k, endl=False)
print "ndis %d nreorder %d" % (hnsw_stats.ndis, hnsw_stats.nreorder)