Method test_22

client/hstest.cpp:1359–1402

}

void
hstest_thread::test_22(int num)
{
  /* dd if=/dev/zero of=dummy.dat bs=1024M count=100 */
  unsigned int id = arg.id;
  std::string err;
  auto_file filefd;
  char fname[1024];
  snprintf(fname, sizeof(fname), "dummy.dat");
  int open_flags = O_RDONLY | O_DIRECT;
  filefd.reset(open(fname, open_flags, 0644));
  if (filefd.get() < 0) {
    fprintf(stderr, "open: %s: %d %s\n", fname, errno, strerror(errno));
    return;
  }
  char buf_x[4096 * 2];
  char *const buf = (char *)(size_t(buf_x + 4096) / 4096 * 4096);
  unsigned long long count = 0;
  drand48_data randbuf;
  unsigned long long seed = time(0);
  seed *= 10;
  seed += id;
  srand48_r(seed, &randbuf);
  for (unsigned int i = 0; i < arg.sh.loop; ++i) {
    double kf = 0;
    drand48_r(&randbuf, &kf);
    kf *= (209715200 / 1);
    // fprintf(stderr, "v=%f\n", kf);
    off_t v = static_cast<off_t>(kf);
    v %= (209715200 / 1);
    v *= (512 * 1);
    const double tm1 = gettimeofday_double();
    const ssize_t r = pread(filefd.get(), buf, (512 * 1), v);
    const double tm2 = gettimeofday_double();
    if (r < 0) {
      fprintf(stderr, "pread: %s: %d %s\n", fname, errno, strerror(errno));
      return;
    }
    ++count;
    ++op_success_count;
    arg.sh.increment_count();
    set_timing(tm2 - tm1);
  }
}

void
hstest_thread::operator ()()