fsync_bench.c

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <sys/time.h>

int main(int argc, const char *argv[])
{
	if (argc > 2) {
		printf("Usage: %s [count]", argv[0]);
		exit(EX_USAGE);
	}

	char template[] = "tmpXXXXXX";
	int fd = mkstemp(template);
	if (fd < 0) {
		perror("Unable to create temp file");
		exit(EX_OSERR);
	}
	unlink(template);

	struct timeval start, stop;
	gettimeofday(&start, NULL);

	int i = argc == 2 ? atoi(argv[1]) : 1000;
	double count = i;

	while (i-- > 0) {
		(void)write(1, ".", 1);
		if (write(fd, "x", 1) < 1) {
			perror("write");
			exit(EX_OSERR);
		}
		fsync(fd);
	}

	gettimeofday(&stop, NULL);
	printf ("\nIOPS: %f\n", count * 1000000 / (1000000 * (stop.tv_sec - start.tv_sec) +
						 (stop.tv_usec - start.tv_usec)));
	return EX_OK;
}