C script that consumes memory, 512M per 512M, every time it runs, it'll consume 512M of RAM:

ram_consume.c

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>

#define K 1024
#define M 1024*K

#define MAX_MEM 500
#define BLK_SIZE M
int main() {
uint8_t *p = malloc(MAX_MEM*1024*1024);
unsigned long i=0;

if (!p) {
 printf("argh!\n");
 return 1;
}

for (i=0;i<MAX_MEM;i++) {
	printf("MB=%ld\n",i);
	memset(p,0,1024*1024);
	p+=BLK_SIZE;
}

while(1) {
	sleep(10);
}
}