代码

#include <cstdio>
#include <unistd.h>
static inline unsigned long long rdtsc_(void) { unsigned lo, hi; __asm__ __volatile__("rdtsc" : "=a"(lo), "=d"(hi)); return ((unsigned long long)hi << 32) | lo; }
static char pad[122912768];
int main(){
  long v = 30000;
  volatile char* p = pad;
  for (long i=0;i<v;i++) p[i*4096]=1;
  { unsigned long long t0=rdtsc_(); while (rdtsc_()-t0 < 50ULL*3000000ULL) {} }
  return 0;
}

评测结果