* gcc -o iotest io.c
*/
+#include <assert.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <sys/time.h>
#include <assert.h>
#include <stdlib.h>
+#include <stdint.h>
#include <stdio.h>
-int tsize = 1000 * 1048576;
-const char *path = "/tmp/wt.dat";
+static int c = 0;
+static int tsize = 1000 * 1048576;
+static const char path[] = "/tmp/wt.dat";
+static char buf[65536];
-int c = 0;
+static uint64_t now(void) {
+ struct timeval tv;
-char* bufit(size_t l)
-{
- char *p = malloc(l);
- memset(p, '!', l);
- return p;
+ if (gettimeofday(&tv, NULL))
+ abort();
+
+ return tv.tv_sec * 1000000ULL + tv.tv_usec;
}
-void writetest(int size, size_t bsize)
+static void writetest(int size, size_t bsize)
{
int i;
- char *buf = bufit(bsize);
- struct timeval start, end;
+ uint64_t start, end;
double elapsed;
double mbps;
+ assert(bsize <= sizeof buf);
+
int fd = open(path, O_CREAT|O_WRONLY, 0644);
if (fd < 0) {
perror("open failed");
exit(254);
}
- assert(0 == gettimeofday(&start, NULL));
+ start = now();
+
for (i = 0; i < size; i += bsize) {
int rv = write(fd, buf, bsize);
if (c++ % 2000 == 0) fprintf(stderr, ".");
exit(254);
}
}
-#ifdef __linux__
+ close(fd);
+
+#ifndef NSYNC
+# ifdef __linux__
fdatasync(fd);
-#else
+# else
fsync(fd);
-#endif
- close(fd);
- assert(0 == gettimeofday(&end, NULL));
- elapsed = (end.tv_sec - start.tv_sec) + ((double)(end.tv_usec - start.tv_usec))/100000.;
+# endif
+#endif /* SYNC */
+
+ end = now();
+ elapsed = (end - start) / 1e6;
mbps = ((tsize/elapsed)) / 1048576;
- fprintf(stderr, "\nWrote %d bytes in %03fs using %ld byte buffers: %03fmB/s\n", size, elapsed, bsize, mbps);
- free(buf);
+ fprintf(stderr, "\nWrote %d bytes in %03fs using %ld byte buffers: %03fmB/s\n", size, elapsed, bsize, mbps);
}
void readtest(int size, size_t bsize)
{
int i;
- char *buf = bufit(bsize);
- struct timeval start, end;
+ uint64_t start, end;
double elapsed;
double mbps;
+ assert(bsize <= sizeof buf);
+
int fd = open(path, O_RDONLY, 0644);
if (fd < 0) {
perror("open failed");
exit(254);
}
- assert(0 == gettimeofday(&start, NULL));
+ start = now();
+
for (i = 0; i < size; i += bsize) {
int rv = read(fd, buf, bsize);
if (rv < 0) {
}
}
close(fd);
- assert(0 == gettimeofday(&end, NULL));
- elapsed = (end.tv_sec - start.tv_sec) + ((double)(end.tv_usec - start.tv_usec))/100000.;
+
+ end = now();
+ elapsed = (end - start) / 1e6;
mbps = ((tsize/elapsed)) / 1048576;
- fprintf(stderr, "Read %d bytes in %03fs using %ld byte buffers: %03fmB/s\n", size, elapsed, bsize, mbps);
- free(buf);
+ fprintf(stderr, "Read %d bytes in %03fs using %ld byte buffers: %03fmB/s\n", size, elapsed, bsize, mbps);
}
void cleanup() {