void *
rw4k_thread(void *p)
{
struct RR *rr = (typeof(rr))p;
uint8_t * const buf = alloc_buf(rr);
uint64_t cap = 0;
ioctl(rr->fd, BLKGETSIZE64, &cap);
if (cap == 0) {
cap = lseek(rr->fd, 0, SEEK_END);
}
assert(cap);
cap = (rr->perc * (double)cap);
setup_affinity(rr);
const uint64_t start = debug_time_usec();
const uint64_t dur = rr->duration_sec * 1000000;
uint64_t count = 0;
const uint64_t round = 10;
for (;;) {
for (uint64_t i = 0; i < round; i++) {
do_random_rw(rr->fd, rr->mask, buf, rr->write, cap);
}
count += round;
if (debug_time_usec() - start > dur) break;
}
// record
rr->nr_io = count;
free(buf);
pthread_exit(NULL);
}
static inline ssize_t
do_random_rw(const int fd, const size_t mask, uint8_t * const buf, const bool is_write, const uint64_t cap) {
const size_t size = (mask + 1u);
const off_t off = (random_uint64() % (cap - size)) & (~mask);
const uint64_t t0 = debug_time_usec();
const ssize_t r = is_write?pwrite(fd, buf, size, off):pread(fd, buf, size, off);
assert((typeof(size))r == size);
const uint64_t dt = debug_diff_usec(t0);
latency_record(dt, latency);
return r;
}
uint64_t
debug_diff_usec(const uint64_t last)
{
return debug_time_usec() - last;
}
double
debug_time_sec(void)
{
const uint64_t usec = debug_time_usec();
return ((double)usec) / 1000000.0;
}