-
Notifications
You must be signed in to change notification settings - Fork 0
/
smle.c
49 lines (35 loc) · 1.34 KB
/
smle.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
#include <stdio.h>
#include <sys/mman.h> // Needed for mlockall()
#include <unistd.h> // needed for sysconf(int name);
#include <malloc.h>
#include <sys/time.h> // needed for getrusage
#include <sys/resource.h> // needed for getrusage
#define SOMESIZE (100*1024) // 100kB
int main(int argc, char* argv[])
{
// Allocate some memory
int i, page_size;
char* buffer;
struct rusage usage;
// Now lock all current and future pages from preventing of being paged
if (mlockall(MCL_CURRENT | MCL_FUTURE ))
{
perror("mlockall failed:");
}
page_size = sysconf(_SC_PAGESIZE);
buffer = malloc(SOMESIZE);
// Touch each page in this piece of memory to get it mapped into RAM
for (i=0; i < SOMESIZE; i+=page_size)
{
// Each write to this buffer will generate a pagefault.
// Once the pagefault is handled a page will be locked in memory and never
// given back to the system.
buffer[i] = 0;
// print the number of major and minor pagefaults this application has triggered
getrusage(RUSAGE_SELF, &usage);
printf("Major-pagefaults:%d, Minor Pagefaults:%d\n", usage.ru_majflt, usage.ru_minflt);
}
// buffer is never released, or swapped, so using it from now will never lead to any pagefault
//<do your RT-thing>
return 0;
}