// multi-thread
- for (uint32_t n_threads = 1; n_threads <= std::thread::hardware_concurrency(); n_threads++) {
+ for (uint32_t k = 1; k <= n_threads; k++) {
char * src = (char *) malloc(size);
char * dst = (char *) malloc(size);
double tsum = 0.0;
auto helper = [&](int th) {
- const int64_t i0 = (th + 0)*size/n_threads;
- const int64_t i1 = (th + 1)*size/n_threads;
+ const int64_t i0 = (th + 0)*size/k;
+ const int64_t i1 = (th + 1)*size/k;
for (size_t i = 0; i < n; i++) {
memcpy(dst + i0, src + i0, i1 - i0);
const int64_t t0 = ggml_time_us();
- std::vector<std::thread> threads(n_threads - 1);
- for (uint32_t th = 0; th < n_threads - 1; ++th) {
+ std::vector<std::thread> threads(k - 1);
+ for (uint32_t th = 0; th < k - 1; ++th) {
threads[th] = std::thread(helper, th);
}
- helper(n_threads - 1);
+ helper(k - 1);
- for (uint32_t th = 0; th < n_threads - 1; ++th) {
+ for (uint32_t th = 0; th < k - 1; ++th) {
threads[th].join();
}
tsum += (t1 - t0)*1e-6;
- snprintf(strbuf, sizeof(strbuf), "memcpy: %7.2f GB/s (%2d thread)\n", (double) (n*size)/(tsum*1e9), n_threads);
+ snprintf(strbuf, sizeof(strbuf), "memcpy: %7.2f GB/s (%2d thread)\n", (double) (n*size)/(tsum*1e9), k);
s += strbuf;
// needed to prevent the compiler from optimizing the memcpy away