memory_test/madvise.c

58 lines
1.1 KiB
C

#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <sys/time.h>
unsigned long long tv_to_ms(struct timeval tv)
{
return tv.tv_sec * 1000 + tv.tv_usec / 1000;
}
void main()
{
char c;
pid_t pid;
int i;
int j = 0;
struct timeval tv_b, tv_e;;
#define SIZE 100*1024*1024
unsigned long *p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (!p) {
perror("fail to get memory");
exit(-1);
}
madvise(p, SIZE, MADV_HUGEPAGE);
for (j = 0; j < SIZE / 8; j+=128)
*(p + j) = j;
for (i = 0; i < 3; i++) {
gettimeofday(&tv_b, NULL);
madvise(p, SIZE, MADV_PAGEOUT);
gettimeofday(&tv_e, NULL);
printf("swp out bandwidth: %ld bytes/ms\n",
SIZE/(tv_to_ms(tv_e) - tv_to_ms(tv_b)));
gettimeofday(&tv_b, NULL);
for (j = 0; j < SIZE / 8; j+=128)
*(p + j) = j;
gettimeofday(&tv_e, NULL);
printf("swp in bandwidth: %ld bytes/ms\n",
SIZE/(tv_to_ms(tv_e) - tv_to_ms(tv_b)));
}
//madvise(p, SIZE, MADV_PAGEOUT);
//while(1) {
// sleep(100);
//}
}