13 const size_t size_start = 64;
14 const size_t size_end = 16 * (1ull << 20);
15 const size_t samples = 2048;
16 size_t size_per_test = 64 * (1ull << 20);
19 void __attribute__((noinline)) memcpy_noinline(void *dst, void *src, size_t size);
20 void __attribute__((noinline)) memset_noinline(void *dst, int value, size_t size);
21 uint64_t __attribute__((noinline)) sum(volatile void *src, size_t size);
29 int main(int argc, char *argv[])
33 cerr << "memcpy_perf [--memcpy|--memset|--sum]" << endl;
36 if (string(argv[1]) == string("--memcpy")) {
38 } else if (string(argv[1]) == string("--memset")) {
40 } else if (string(argv[1]) == string("--sum")) {
46 unique_ptr<uint8_t[]> src(new uint8_t[size_end]);
47 unique_ptr<uint8_t[]> dst(new uint8_t[size_end]);
48 memset(src.get(), 1, size_end);
50 double start_pow = log10(size_start);
51 double end_pow = log10(size_end);
52 double pow_inc = (end_pow - start_pow) / samples;
54 //cout << "src: " << (uintptr_t)src.get() << endl;
55 //cout << "dst: " << (uintptr_t)dst.get() << endl;
57 for (double cur_pow = start_pow; cur_pow <= end_pow; cur_pow += pow_inc) {
58 chrono::time_point<chrono::high_resolution_clock> copy_start, copy_end;
60 size_t cur_size = (size_t)pow(10.0, cur_pow);
61 size_t iter_per_size = size_per_test / cur_size;
66 memcpy_noinline(src.get(), dst.get(), cur_size);
67 memset_noinline(dst.get(), 0xdeadbeef, cur_size);
68 copy_start = chrono::high_resolution_clock::now();
69 for (int i = 0; i < iter_per_size; i++) {
70 memset_noinline(dst.get(), 0xdeadbeef, cur_size);
72 copy_end = chrono::high_resolution_clock::now();
76 memcpy_noinline(dst.get(), src.get(), cur_size);
77 memcpy_noinline(src.get(), dst.get(), cur_size);
78 copy_start = chrono::high_resolution_clock::now();
79 for (int i = 0; i < iter_per_size; i++) {
80 memcpy_noinline(dst.get(), src.get(), cur_size);
82 copy_end = chrono::high_resolution_clock::now();
87 s += sum(src.get(), cur_size);
88 copy_start = chrono::high_resolution_clock::now();
89 for (int i = 0; i < iter_per_size; i++) {
90 s += sum(src.get(), cur_size);
92 copy_end = chrono::high_resolution_clock::now();
98 double ns_per_copy = chrono::duration_cast<chrono::nanoseconds>(copy_end - copy_start).count() / double(iter_per_size);
99 double gb_per_sec = ((double)cur_size / (1ull<<30)) / (ns_per_copy / 1.0E9);
100 if (type == MemcpyBench)
102 cout << "size: " << cur_size << ", perf: " << gb_per_sec << "GB/s, iter: " << iter_per_size << endl;