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#include <chrono>
#include <cstdlib>
#include <iostream>
#include <sstream>
#include <string>
#include <vector>
#include "gsd.h"
int main(int argc, char** argv) // NOLINT
{
const size_t n_keys = 40000;
const size_t max_frames = 100;
std::vector<char> data;
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());
}
gsd_handle handle;
gsd_open(&handle, "test.gsd", GSD_OPEN_READONLY);
size_t const n_frames = gsd_get_nframes(&handle);
size_t n_read = n_frames;
if (n_read > max_frames)
{
n_read = max_frames;
}
std::cout << "Reading test.gsd with: " << n_keys << " keys and " << n_frames << " frames."
<< '\n';
auto t1 = std::chrono::high_resolution_clock::now();
for (size_t frame = 0; frame < n_read; frame++)
{
for (auto const& name : names)
{
const gsd_index_entry* e;
e = gsd_find_chunk(&handle, frame, name.c_str());
if (data.empty())
{
data.resize(e->N * e->M * gsd_sizeof_type((gsd_type)e->type));
}
gsd_read_chunk(&handle, data.data(), e);
}
}
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_read);
const double us = 1e-6;
std::cout << "Sequential read time: " << time_per_key / us << " microseconds/key." << '\n';
gsd_close(&handle);
}
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