ioperf/hdf5/hdf5perf.c

#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <glib.h>
#include <hdf5.h>


static const int WIDTH = 2048;
static const int HEIGHT = 2048;
static const int N_DARKS = 10;
static const int N_FLATS = 10;
static const int N_PROJS = 200;


static void
write_dataset (hid_t file, const char *name, const guint16 *data, int n_items)
{
    GTimer *timer;
    hid_t datatype;
    hid_t dataspace;
    hid_t dataset;
    hsize_t dims[3];

    timer = g_timer_new ();

    dims[0] = WIDTH;
    dims[1] = HEIGHT;
    dims[2] = n_items;

    datatype = H5Tcopy (H5T_STD_U16LE);

    dataspace = H5Screate_simple (3, dims, NULL);
    dataset = H5Dcreate (file, name, datatype, dataspace, H5P_DEFAULT);
    H5Dwrite (dataset, H5T_STD_U16LE, H5S_ALL, H5S_ALL, H5P_DEFAULT, data);

    H5Sclose (dataspace);
    H5Dclose (dataset);
    H5Tclose (datatype);
    g_timer_destroy (timer);
}

static void
create_individual_data_sets (hid_t file, const guint16 *data)
{
    write_dataset (file, "projs", data, N_PROJS);
    write_dataset (file, "darks", data, N_DARKS);
    write_dataset (file, "flats", data, N_FLATS);
}

static void
create_single_dataset (hid_t file, const guint16 *data)
{
    write_dataset (file, "all", data, N_DARKS + N_FLATS + N_PROJS);
}

static gdouble
run (void (*func)(hid_t, const guint16 *), const char *fname, const guint16 *data)
{
    hid_t file;
    int fid;
    GTimer *timer;
    gdouble elapsed;

    timer = g_timer_new ();

    g_timer_start (timer);
    file = H5Fcreate (fname, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);

    func (file, data);

    H5Fflush (file, H5F_SCOPE_GLOBAL);
    H5Fclose (file);

    /* H5Fflush is extremely unreliable. So let's take out the hammer ... */
    fid = open (fname, O_RDWR | O_SYNC);
    fsync (fid);
    close (fid);

    g_timer_stop (timer);
    elapsed = g_timer_elapsed (timer, NULL);
    g_timer_destroy (timer);
    return elapsed;
}

int
main (int argc, char const* argv[])
{
    guint16 *data;
    gsize size;

    size = 2 * WIDTH * HEIGHT * (N_DARKS + N_FLATS + N_PROJS);
    data = g_malloc (size);

    g_print ("Single data set: %f MB/s\n",
             ((gdouble) size) / 1024. / 1024. / run (create_single_dataset, "bar.h5", data));

    g_print ("Multi data set: %f MB/s\n",
             ((gdouble) size) / 1024. / 1024. / run (create_individual_data_sets, "foo.h5", data));

    g_free (data);
    return 0;
}