faiss/tests/test_partition.py
Matthijs Douze 6d0bc58db6 Implementation of PQ4 search with SIMD instructions (#1542)
Summary:
IndexPQ and IndexIVFPQ implementations with AVX shuffle instructions.

The training and computing of the codes does not change wrt. the original PQ versions but the code layout is "packed" so that it can be used efficiently by the SIMD computation kernels.

The main changes are:

- new IndexPQFastScan and IndexIVFPQFastScan objects

- simdib.h for an abstraction above the AVX2 intrinsics

- BlockInvertedLists for invlists that are 32-byte aligned and where codes are not sequential

- pq4_fast_scan.h/.cpp:  for packing codes and look-up tables + optmized distance comptuation kernels

- simd_result_hander.h: SIMD version of result collection in heaps / reservoirs

Misc changes:

- added contrib.inspect_tools to access fields in C++ objects

- moved .h and .cpp code for inverted lists to an invlists/ subdirectory, and made a .h/.cpp for InvertedListsIOHook

- added a new inverted lists type with 32-byte aligned codes (for consumption by SIMD)

- moved Windows-specific intrinsics to platfrom_macros.h

Pull Request resolved: https://github.com/facebookresearch/faiss/pull/1542

Test Plan:
```
buck test mode/opt  -j 4  //faiss/tests/:test_fast_scan_ivf //faiss/tests/:test_fast_scan
buck test mode/opt  //faiss/manifold/...
```

Reviewed By: wickedfoo

Differential Revision: D25175439

Pulled By: mdouze

fbshipit-source-id: ad1a40c0df8c10f4b364bdec7172e43d71b56c34
2020-12-03 10:06:38 -08:00

348 lines
10 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.
import numpy as np
import faiss
import unittest
class PartitionTests:
def test_partition(self):
self.do_partition(160, 80)
def test_partition_manydups(self):
self.do_partition(160, 80, maxval=16)
def test_partition_lowq(self):
self.do_partition(160, 10, maxval=16)
def test_partition_highq(self):
self.do_partition(165, 155, maxval=16)
def test_partition_q10(self):
self.do_partition(32, 10, maxval=500)
def test_partition_q10_dups(self):
self.do_partition(32, 10, maxval=16)
def test_partition_q10_fuzzy(self):
self.do_partition(32, (10, 15), maxval=500)
def test_partition_fuzzy(self):
self.do_partition(160, (70, 80), maxval=500)
def test_partition_fuzzy_2(self):
self.do_partition(160, (70, 80))
class TestPartitioningFloat(unittest.TestCase, PartitionTests):
def do_partition(self, n, q, maxval=None, seed=None):
if seed is None:
for i in range(50):
self.do_partition(n, q, maxval, i + 1234)
# print("seed=", seed)
rs = np.random.RandomState(seed)
if maxval is None:
vals = rs.rand(n).astype('float32')
else:
vals = rs.randint(maxval, size=n).astype('float32')
ids = (rs.permutation(n) + 12345).astype('int64')
dic = dict(zip(ids, vals))
vals_orig = vals.copy()
sp = faiss.swig_ptr
if type(q) == int:
faiss.CMax_float_partition_fuzzy(
sp(vals), sp(ids), n,
q, q, None
)
else:
q_min, q_max = q
q = np.array([-1], dtype='uint64')
faiss.CMax_float_partition_fuzzy(
sp(vals), sp(ids), n,
q_min, q_max, sp(q)
)
q = q[0]
assert q_min <= q <= q_max
o = vals_orig.argsort()
thresh = vals_orig[o[q]]
n_eq = (vals_orig[o[:q]] == thresh).sum()
for i in range(q):
self.assertEqual(vals[i], dic[ids[i]])
self.assertLessEqual(vals[i], thresh)
if vals[i] == thresh:
n_eq -= 1
self.assertEqual(n_eq, 0)
class TestPartitioningFloatMin(unittest.TestCase, PartitionTests):
def do_partition(self, n, q, maxval=None, seed=None):
if seed is None:
for i in range(50):
self.do_partition(n, q, maxval, i + 1234)
# print("seed=", seed)
rs = np.random.RandomState(seed)
if maxval is None:
vals = rs.rand(n).astype('float32')
mirval = 1.0
else:
vals = rs.randint(maxval, size=n).astype('float32')
mirval = 65536
ids = (rs.permutation(n) + 12345).astype('int64')
dic = dict(zip(ids, vals))
vals_orig = vals.copy()
vals[:] = mirval - vals
sp = faiss.swig_ptr
if type(q) == int:
faiss.CMin_float_partition_fuzzy(
sp(vals), sp(ids), n,
q, q, None
)
else:
q_min, q_max = q
q = np.array([-1], dtype='uint64')
faiss.CMin_float_partition_fuzzy(
sp(vals), sp(ids), n,
q_min, q_max, sp(q)
)
q = q[0]
assert q_min <= q <= q_max
vals[:] = mirval - vals
o = vals_orig.argsort()
thresh = vals_orig[o[q]]
n_eq = (vals_orig[o[:q]] == thresh).sum()
for i in range(q):
np.testing.assert_almost_equal(vals[i], dic[ids[i]], decimal=5)
self.assertLessEqual(vals[i], thresh)
if vals[i] == thresh:
n_eq -= 1
self.assertEqual(n_eq, 0)
class TestPartitioningUint16(unittest.TestCase, PartitionTests):
def do_partition(self, n, q, maxval=65536, seed=None):
if seed is None:
for i in range(50):
self.do_partition(n, q, maxval, i + 1234)
# print("seed=", seed)
rs = np.random.RandomState(seed)
vals = rs.randint(maxval, size=n).astype('uint16')
ids = (rs.permutation(n) + 12345).astype('int64')
dic = dict(zip(ids, vals))
sp = faiss.swig_ptr
vals_orig = vals.copy()
tab_a = faiss.AlignedTableUint16()
faiss.copy_array_to_AlignedTable(vals, tab_a)
# print("tab a type", tab_a.get())
if type(q) == int:
thresh2 = faiss.CMax_uint16_partition_fuzzy(
tab_a.get(), sp(ids), n, q, q, None)
else:
q_min, q_max = q
q = np.array([-1], dtype='uint64')
thresh2 = faiss.CMax_uint16_partition_fuzzy(
tab_a.get(), sp(ids), n,
q_min, q_max, sp(q)
)
q = q[0]
assert q_min <= q <= q_max
vals = faiss.AlignedTable_to_array(tab_a)
o = vals_orig.argsort()
thresh = vals_orig[o[q]]
n_eq = (vals_orig[o[:q]] == thresh).sum()
for i in range(q):
self.assertEqual(vals[i], dic[ids[i]])
self.assertLessEqual(vals[i], thresh)
if vals[i] == thresh:
n_eq -= 1
self.assertEqual(n_eq, 0)
class TestPartitioningUint16Min(unittest.TestCase, PartitionTests):
def do_partition(self, n, q, maxval=65536, seed=None):
#seed = 1235
if seed is None:
for i in range(50):
self.do_partition(n, q, maxval, i + 1234)
# print("seed=", seed)
rs = np.random.RandomState(seed)
vals = rs.randint(maxval, size=n).astype('uint16')
ids = (rs.permutation(n) + 12345).astype('int64')
dic = dict(zip(ids, vals))
sp = faiss.swig_ptr
vals_orig = vals.copy()
tab_a = faiss.AlignedTableUint16()
vals_inv = (65535 - vals).astype('uint16')
faiss.copy_array_to_AlignedTable(vals_inv, tab_a)
# print("tab a type", tab_a.get())
if type(q) == int:
thresh2 = faiss.CMin_uint16_partition_fuzzy(
tab_a.get(), sp(ids), n, q, q, None)
else:
q_min, q_max = q
q = np.array([-1], dtype='uint64')
thresh2 = faiss.CMin_uint16_partition_fuzzy(
tab_a.get(), sp(ids), n,
q_min, q_max, sp(q)
)
q = q[0]
assert q_min <= q <= q_max
vals_inv = faiss.AlignedTable_to_array(tab_a)
vals = 65535 - vals_inv
o = vals_orig.argsort()
thresh = vals_orig[o[q]]
n_eq = (vals_orig[o[:q]] == thresh).sum()
for i in range(q):
self.assertEqual(vals[i], dic[ids[i]])
self.assertLessEqual(vals[i], thresh)
if vals[i] == thresh:
n_eq -= 1
self.assertEqual(n_eq, 0)
class TestHistograms(unittest.TestCase):
def do_test(self, nbin, n):
rs = np.random.RandomState(123)
tab = rs.randint(nbin, size=n).astype('uint16')
ref_histogram = np.bincount(tab, minlength=nbin)
tab_a = faiss.AlignedTableUint16()
faiss.copy_array_to_AlignedTable(tab, tab_a)
sp = faiss.swig_ptr
hist = np.zeros(nbin, 'int32')
if nbin == 8:
faiss.simd_histogram_8(tab_a.get(), n, 0, -1, sp(hist))
elif nbin == 16:
faiss.simd_histogram_16(tab_a.get(), n, 0, -1, sp(hist))
else:
raise AssertionError()
np.testing.assert_array_equal(hist, ref_histogram)
def test_8bin_even(self):
self.do_test(8, 5 * 16)
def test_8bin_odd(self):
self.do_test(8, 123)
def test_16bin_even(self):
self.do_test(16, 5 * 16)
def test_16bin_odd(self):
self.do_test(16, 123)
def do_test_bounded(self, nbin, n, shift=2, minv=500, rspan=None, seed=None):
if seed is None:
for run in range(50):
self.do_test_bounded(nbin, n, shift, minv, rspan, seed=123 + run)
return
if rspan is None:
rmin, rmax = 0, nbin * 6
else:
rmin, rmax = rspan
rs = np.random.RandomState(seed)
tab = rs.randint(rmin, rmax, size=n).astype('uint16')
bc = np.bincount(tab, minlength=65536)
binsize = 1 << shift
ref_histogram = bc[minv : minv + binsize * nbin]
def pad_and_reshape(x, m, n):
xout = np.zeros(m * n, dtype=x.dtype)
xout[:x.size] = x
return xout.reshape(m, n)
ref_histogram = pad_and_reshape(ref_histogram, nbin, binsize)
ref_histogram = ref_histogram.sum(1)
tab_a = faiss.AlignedTableUint16()
faiss.copy_array_to_AlignedTable(tab, tab_a)
sp = faiss.swig_ptr
hist = np.zeros(nbin, 'int32')
if nbin == 8:
faiss.simd_histogram_8(
tab_a.get(), n, minv, shift, sp(hist)
)
elif nbin == 16:
faiss.simd_histogram_16(
tab_a.get(), n, minv, shift, sp(hist)
)
else:
raise AssertionError()
np.testing.assert_array_equal(hist, ref_histogram)
def test_8bin_even_bounded(self):
self.do_test_bounded(8, 22 * 16)
def test_8bin_odd_bounded(self):
self.do_test_bounded(8, 10000)
def test_16bin_even_bounded(self):
self.do_test_bounded(16, 22 * 16)
def test_16bin_odd_bounded(self):
self.do_test_bounded(16, 10000)
def test_16bin_bounded_bigrange(self):
self.do_test_bounded(16, 1000, shift=12, rspan=(10, 65500))
def test_8bin_bounded_bigrange(self):
self.do_test_bounded(8, 1000, shift=13, rspan=(10, 65500))
def test_16bin_bounded_bigrange_2(self):
self.do_test_bounded(16, 10, shift=12, rspan=(65000, 65500))
def test_16bin_bounded_shift0(self):
self.do_test_bounded(16, 10000, shift=0, rspan=(10, 65500))
def test_8bin_bounded_shift0(self):
self.do_test_bounded(8, 10000, shift=0, rspan=(10, 65500))
def test_16bin_bounded_ignore_out_range(self):
self.do_test_bounded(16, 10000, shift=5, rspan=(100, 20000), minv=300)
def test_8bin_bounded_ignore_out_range(self):
self.do_test_bounded(8, 10000, shift=5, rspan=(100, 20000), minv=300)