-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathbenchmark.cpp
190 lines (151 loc) · 6.17 KB
/
benchmark.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
#include <algorithm>
#include <chrono>
#include <iomanip>
#include <iostream>
#include <random>
#include <vector>
#include <cmath> // For: fabs
#include <cblas.h>
#ifndef MAX_SPEED
#error "Must set max speed with -DMAX_SPEED=... or similar"
#endif
extern "C" {
/* Your function must have the following signature: */
extern const char* dgemm_desc;
extern void square_dgemm(int, double*, double*, double*);
}
void reference_dgemm(int n, double alpha, double* A, double* B, double* C) {
cblas_dgemm(CblasColMajor, CblasNoTrans, CblasNoTrans, n, n, n, alpha, A, n, B, n, 1., C, n);
}
void fill(double* p, int n) {
static std::random_device rd;
static std::default_random_engine gen(rd());
static std::uniform_real_distribution<> dis(-1.0, 1.0);
for (int i = 0; i < n; ++i)
p[i] = 2 * dis(gen) - 1;
}
void fill_deterministic(double* p, int n) {
for (int i = 0; i < n; ++i)
p[i] = i + 1.0;
}
void fill_zero(double* p, int n) {
for (int i = 0; i < n; ++i)
p[i] = 0.0;
}
void fill_identity(double* p, int n) {
for (int i = 0; i < 10; ++i) {
for (int j = 0; j < 10; j++) {
if (i == j) {
p[i*10 + j]= 1.0;
} else {
p[i*10 + j] = 0.0;
}
}
}
}
/* The benchmarking program */
int main(int argc, char** argv) {
std::cout << "Description:\t" << dgemm_desc << std::endl << std::endl;
std::cout << std::fixed << std::setprecision(2);
/* Test sizes should highlight performance dips at multiples of certain powers-of-two */
#ifdef ALL_SIZES
/* Multiples-of-32, +/- 1. */
std::vector<int> test_sizes{
31, 32, 33, 63, 64, 65, 95, 96, 97, 127, 128, 129, 159, 160, 161, 191,
192, 193, 223, 224, 225, 255, 256, 257, 287, 288, 289, 319, 320, 321, 351, 352,
353, 383, 384, 385, 415, 416, 417, 447, 448, 449, 479, 480, 481, 511, 512, 513,
543, 544, 545, 575, 576, 577, 607, 608, 609, 639, 640, 641, 671, 672, 673, 703,
704, 705, 735, 736, 737, 767, 768, 769, 799, 800, 801, 831, 832, 833, 863, 864,
865, 895, 896, 897, 927, 928, 929, 959, 960, 961, 991, 992, 993, 1023, 1024, 1025};
#else
/* A representative subset of the first list. */
std::vector<int> test_sizes{31, 32, 96, 97, 127, 128, 129, 191, 192, 229, 255, 256, 257,
319, 320, 321, 417, 479, 480, 511, 512, 639, 640, 767, 768, 769};
#endif
if (argc > 1) {
test_sizes.clear();
std::transform(&argv[1], &argv[argc], std::back_inserter(test_sizes), [](char* arg) {
size_t end;
int size = std::stoi(arg, &end);
if (arg[end] != '\0' || size < 1) {
throw std::invalid_argument("all arguments must be positive numbers");
}
return size;
});
}
std::sort(test_sizes.begin(), test_sizes.end());
int nsizes = test_sizes.size();
/* assume last size is also the largest size */
int nmax = test_sizes[nsizes - 1];
/* allocate memory for all problems */
std::vector<double> buf(3 * nmax * nmax);
std::vector<double> per;
/* For each test size */
for (int n : test_sizes) {
/* Create and fill 3 random matrices A,B,C*/
double* A = buf.data() + 0;
double* B = A + nmax * nmax;
double* C = B + nmax * nmax;
fill(A, n * n);
fill(B, n * n);
fill(C, n * n);
/* Measure performance (in Gflops/s). */
/* Time a "sufficiently long" sequence of calls to reduce noise */
double Gflops_s = 0.0, seconds = -1.0;
double timeout = 0.1; // "sufficiently long" := at least 1/10 second.
for (int n_iterations = 1; seconds < timeout; n_iterations *= 2) {
/* Warm-up */
square_dgemm(n, A, B, C);
/* Benchmark n_iterations runs of square_dgemm */
auto start = std::chrono::steady_clock::now();
for (int it = 0; it < n_iterations; ++it) {
square_dgemm(n, A, B, C);
}
auto end = std::chrono::steady_clock::now();
std::chrono::duration<double> diff = end - start;
seconds = diff.count();
/* compute Gflop/s rate */
Gflops_s = 2.e-9 * n_iterations * n * n * n / seconds;
}
/* Storing Mflop rate and calculating percentage of peak */
double Mflops_s = Gflops_s * 1000;
per.push_back(Gflops_s * 100 / MAX_SPEED);
std::cout << "Size: " << n //
<< "\tMflops/s: " << Mflops_s //
<< "\tPercentage: " << per.back() //
<< std::endl;
/* Ensure that error does not exceed the theoretical error bound. */
/* C := A * B, computed with square_dgemm */
std::fill(C, &C[n * n], 0.0);
square_dgemm(n, A, B, C);
/* Do not explicitly check that A and B were unmodified on square_dgemm exit
* - if they were, the following will most likely detect it:
* C := C - A * B, computed with reference_dgemm */
reference_dgemm(n, -1., A, B, C);
/* A := |A|, B := |B|, C := |C| */
std::transform(A, &A[n * n], A, fabs);
std::transform(B, &B[n * n], B, fabs);
std::transform(C, &C[n * n], C, fabs);
/* C := |C| - 3 * e_mach * n * |A| * |B|, computed with reference_dgemm */
const auto e_mach = std::numeric_limits<double>::epsilon();
reference_dgemm(n, -3. * e_mach * n, A, B, C);
/* If any element in C is positive, then something went wrong in square_dgemm */
for (int i = 0; i < n * n; ++i) {
if (C[i] > 0) {
std::cerr << "*** FAILURE *** Error in matrix multiply exceeds componentwise error "
"bounds."
<< std::endl;
return 1;
}
}
}
/* Calculating average percentage of peak reached by algorithm */
double aveper = 0;
for (int i = 0; i < nsizes; i++) {
aveper += per[i];
}
aveper /= nsizes;
/* Printing average percentage to screen */
std::cout << "Average percentage of Peak = " << aveper << std::endl;
return 0;
}