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#include <chrono>
#include <cstdlib>
#include <iostream>
#include <sstream>
#include <string>
#include <vector>
#ifdef _WIN32
#include <io.h>
#define fsync _commit
#else // linux / mac
#include <unistd.h>
#endif
#include "gsd.h"
int main(int argc, char** argv) // NOLINT
{
const size_t n_keys = 16;
const size_t n_frames = 100;
const size_t key_size = static_cast<const size_t>(1024) * static_cast<const size_t>(1024);
std::vector<double> data(key_size);
for (size_t i = 0; i < key_size; i++)
{
data[i] = (double)i;
}
std::vector<std::string> names;
for (size_t i = 0; i < n_keys; i++)
{
std::ostringstream s;
s << "log/hpmc/integrate/Sphere/quantity/" << i;
names.push_back(s.str());
}
std::cout << "Writing test.gsd with: " << n_keys << " keys, " << n_frames << " frames, "
<< "and " << key_size << " double(s) per key" << '\n';
gsd_handle handle;
gsd_create_and_open(&handle, "test.gsd", "app", "schema", 0, GSD_OPEN_APPEND, 0);
for (size_t frame = 0; frame < n_frames / 2; frame++)
{
for (auto const& name : names)
{
gsd_write_chunk(&handle, name.c_str(), GSD_TYPE_DOUBLE, key_size, 1, 0, data.data());
}
gsd_end_frame(&handle);
}
fsync(handle.fd);
auto t1 = std::chrono::high_resolution_clock::now();
for (size_t frame = 0; frame < n_frames / 2; frame++)
{
for (auto const& name : names)
{
gsd_write_chunk(&handle, name.c_str(), GSD_TYPE_DOUBLE, key_size, 1, 0, data.data());
}
gsd_end_frame(&handle);
}
fsync(handle.fd);
auto t2 = std::chrono::high_resolution_clock::now();
std::chrono::duration<double> const time_span
= std::chrono::duration_cast<std::chrono::duration<double>>(t2 - t1);
double const time_per_key = time_span.count() / double(n_keys) / double(n_frames / double(2));
const double us = 1e-6;
std::cout << "Write time: " << time_per_key / us << " microseconds/key." << '\n';
std::cout << "Write time: " << time_per_key / us * n_keys << " microseconds/frame." << '\n';
const double mb_per_second
= double(key_size * 8 + static_cast<const size_t>(32) * static_cast<const size_t>(2))
/ 1048576.0 / time_per_key;
std::cout << "MB/s: " << mb_per_second << " MB/s." << '\n';
gsd_close(&handle);
gsd_open(&handle, "test.gsd", GSD_OPEN_READONLY);
std::cout << "Frames: " << gsd_get_nframes(&handle) << '\n';
gsd_close(&handle);
}
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