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@offlinehacker
Created September 14, 2012 21:30
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Disk seek time measure
#define _LARGEFILE64_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <time.h>
#include <signal.h>
#include <sys/fcntl.h>
#include <sys/ioctl.h>
#include <linux/fs.h>
#define BLOCKSIZE 512
#define TIMEOUT 30
int count;
time_t start;
void done()
{
time_t end;
time(&end);
if (end < start + TIMEOUT) {
printf(".");
alarm(1);
return;
}
if (count) {
printf(".\nResults: %d seeks/second, %.2f ms random access time\n",
count / TIMEOUT, 1000.0 * TIMEOUT / count);
}
exit(EXIT_SUCCESS);
}
void handle(const char *string, int error)
{
if (error) {
perror(string);
exit(EXIT_FAILURE);
}
}
int main(int argc, char **argv)
{
char buffer[BLOCKSIZE];
int fd, retval;
unsigned long numblocks;
off64_t offset;
setvbuf(stdout, NULL, _IONBF, 0);
printf("Seeker v2.0, 2007-01-15, "
"http://www.linuxinsight.com/how_fast_is_your_disk.html\n");
if (argc != 2) {
printf("Usage: seeker <raw disk device>\n");
exit(EXIT_SUCCESS);
}
fd = open(argv[1], O_RDONLY);
handle("open", fd < 0);
retval = ioctl(fd, BLKGETSIZE, &numblocks);
handle("ioctl", retval == -1);
printf("Benchmarking %s [%luMB], wait %d seconds",
argv[1], numblocks / 2048, TIMEOUT);
time(&start);
srand(start);
signal(SIGALRM, &done);
alarm(1);
for (;;) {
offset = (off64_t) numblocks * random() / RAND_MAX;
retval = lseek64(fd, BLOCKSIZE * offset, SEEK_SET);
handle("lseek64", retval == (off64_t) -1);
retval = read(fd, buffer, BLOCKSIZE);
handle("read", retval < 0);
count++;
}
/* notreached */
}
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