This is test:
```
uint64_t getnsecs() {
    uint32_t lo, hi;
    __asm__ __volatile__ (
        "rdtsc" : "=a"(lo), "=d"(hi)
    );
    return ((uint64_t)hi << 32) | lo;
}

int main() {
    const int num_iterations = 1;
    uint64_t start, end, total_time = 0;

    start = getnsecs();
    for (int i = 0; i < num_iterations; i++) {
        (void) lrand48();
    }
    end = getnsecs();
    total_time += (end - start);

    printf("Average time for lrand48: %lu cycles\n", total_time /
num_iterations);
    return 0;
}
```
before:
Average time for lrand48: 21418 cycles

after:
Average time for lrand48: 9892 cycles