added benchmarking scripts

benchs/bench_polysemous_sift1m.py

@@ -0,0 +1,82 @@
+
+# Copyright (c) 2015-present, Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under the CC-by-NC license found in the
+# LICENSE file in the root directory of this source tree.
+
+#!/usr/bin/env python2
+
+import time
+import numpy as np
+
+import faiss
+
+#################################################################
+# Small I/O functions
+#################################################################
+
+
+def ivecs_read(fname):
+    a = np.fromfile(fname, dtype='int32')
+    d = a[0]
+    return a.reshape(-1, d + 1)[:, 1:].copy()
+
+
+def fvecs_read(fname):
+    return ivecs_read(fname).view('float32')
+
+
+#################################################################
+#  Main program
+#################################################################
+
+print "load data"
+
+xt = fvecs_read("sift1M/sift_learn.fvecs")
+xb = fvecs_read("sift1M/sift_base.fvecs")
+xq = fvecs_read("sift1M/sift_query.fvecs")
+
+nq, d = xq.shape
+
+print "load GT"
+
+gt = ivecs_read("sift1M/sift_groundtruth.ivecs")
+
+
+# index with 16 subquantizers, 8 bit each
+index = faiss.IndexPQ(d, 16, 8)
+index.do_polysemous_training = True
+index.verbose = True
+
+print "train"
+
+index.train(xt)
+
+print "add vectors to index"
+
+index.add(xb)
+
+nt = 1
+faiss.omp_set_num_threads(1)
+
+
+def evaluate():
+    t0 = time.time()
+    D, I = index.search(xq, 1)
+    t1 = time.time()
+
+    recall_at_1 = (I == gt[:, :1]).sum() / float(nq)
+    print "\t %7.3f ms per query, R@1 %.4f" % (
+        (t1 - t0) * 1000.0 / nq * nt, recall_at_1)
+
+
+print "PQ baseline",
+index.search_type = faiss.IndexPQ.ST_PQ
+evaluate()
+
+for ht in 64, 62, 58, 54, 50, 46, 42, 38, 34, 30:
+    print "Polysemous", ht,
+    index.search_type = faiss.IndexPQ.ST_polysemous
+    index.polysemous_ht = ht
+    evaluate()