#include
#include
+#define FSYNC_FILENAME "/var/tmp/test_fsync.out"
+
/* O_SYNC and O_FSYNC are the same */
#if defined(O_SYNC)
#define OPEN_SYNC_FLAG O_SYNC
struct timeval start_t;
struct timeval elapse_t;
int tmpfile,
- i;
+ i,
+ loops=1000;
char *strout = (char *) malloc(65536);
+ char *filename = FSYNC_FILENAME;
+ if (argc > 2 && strcmp(argv[1],"-f") == 0)
+ {
+ filename = argv[2];
+ argv += 2;
+ argc -= 2;
+ }
+
+ if (argc > 1)
+ loops = atoi(argv[1]);
+
for (i = 0; i < 65536; i++)
strout[i] = 'a';
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | O_CREAT, S_IRUSR | S_IWUSR)) == -1)
+
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR | O_CREAT, S_IRUSR | S_IWUSR)) == -1)
die("can't open /var/tmp/test_fsync.out");
write(tmpfile, strout, 65536);
fsync(tmpfile); /* fsync so later fsync's don't have to do
printf("Simple write timing:\n");
/* write only */
gettimeofday(&start_t, NULL);
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR)) == -1)
- die("can't open /var/tmp/test_fsync.out");
- write(tmpfile, strout, 8192);
- close(tmpfile);
+ for (i = 0; i < loops; i++)
+ {
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR)) == -1)
+ die("can't open /var/tmp/test_fsync.out");
+ write(tmpfile, strout, 8192);
+ close(tmpfile);
+ }
gettimeofday(&elapse_t, NULL);
printf("\twrite ");
print_elapse(start_t, elapse_t);
- printf("\n\n");
+ printf("\n");
- printf("Compare fsync before and after write's close:\n");
+ printf("\nCompare fsync times on write() and non-write() descriptor:\n");
+ printf("(If the times are similar, fsync() can sync data written\n on a different descriptor.)\n");
/* write, fsync, close */
gettimeofday(&start_t, NULL);
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR)) == -1)
- die("can't open /var/tmp/test_fsync.out");
- write(tmpfile, strout, 8192);
- fsync(tmpfile);
- close(tmpfile);
+ for (i = 0; i < loops; i++)
+ {
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR)) == -1)
+ die("can't open /var/tmp/test_fsync.out");
+ write(tmpfile, strout, 8192);
+ fsync(tmpfile);
+ close(tmpfile);
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR)) == -1)
+ die("can't open /var/tmp/test_fsync.out");
+ /* do nothing but the open/close the tests are consistent. */
+ close(tmpfile);
+ }
gettimeofday(&elapse_t, NULL);
printf("\twrite, fsync, close ");
print_elapse(start_t, elapse_t);
/* write, close, fsync */
gettimeofday(&start_t, NULL);
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR)) == -1)
- die("can't open /var/tmp/test_fsync.out");
- write(tmpfile, strout, 8192);
- close(tmpfile);
- /* reopen file */
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR)) == -1)
- die("can't open /var/tmp/test_fsync.out");
- fsync(tmpfile);
- close(tmpfile);
+ for (i = 0; i < loops; i++)
+ {
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR)) == -1)
+ die("can't open /var/tmp/test_fsync.out");
+ write(tmpfile, strout, 8192);
+ close(tmpfile);
+ /* reopen file */
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR)) == -1)
+ die("can't open /var/tmp/test_fsync.out");
+ fsync(tmpfile);
+ close(tmpfile);
+ }
gettimeofday(&elapse_t, NULL);
printf("\twrite, close, fsync ");
print_elapse(start_t, elapse_t);
printf("\nCompare one o_sync write to two:\n");
/* 16k o_sync write */
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | OPEN_SYNC_FLAG)) == -1)
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR | OPEN_SYNC_FLAG)) == -1)
die("can't open /var/tmp/test_fsync.out");
gettimeofday(&start_t, NULL);
- write(tmpfile, strout, 16384);
+ for (i = 0; i < loops; i++)
+ write(tmpfile, strout, 16384);
gettimeofday(&elapse_t, NULL);
close(tmpfile);
printf("\tone 16k o_sync write ");
printf("\n");
/* 2*8k o_sync writes */
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | OPEN_SYNC_FLAG)) == -1)
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR | OPEN_SYNC_FLAG)) == -1)
die("can't open /var/tmp/test_fsync.out");
gettimeofday(&start_t, NULL);
- write(tmpfile, strout, 8192);
- write(tmpfile, strout, 8192);
+ for (i = 0; i < loops; i++)
+ {
+ write(tmpfile, strout, 8192);
+ write(tmpfile, strout, 8192);
+ }
gettimeofday(&elapse_t, NULL);
close(tmpfile);
printf("\ttwo 8k o_sync writes ");
#ifdef OPEN_DATASYNC_FLAG
/* open_dsync, write */
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | O_DSYNC)) == -1)
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR | O_DSYNC)) == -1)
die("can't open /var/tmp/test_fsync.out");
gettimeofday(&start_t, NULL);
- write(tmpfile, strout, 8192);
+ for (i = 0; i < loops; i++)
+ write(tmpfile, strout, 8192);
gettimeofday(&elapse_t, NULL);
close(tmpfile);
printf("\topen o_dsync, write ");
printf("\n");
/* open_fsync, write */
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | OPEN_SYNC_FLAG)) == -1)
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR | OPEN_SYNC_FLAG)) == -1)
die("can't open /var/tmp/test_fsync.out");
gettimeofday(&start_t, NULL);
- write(tmpfile, strout, 8192);
+ for (i = 0; i < loops; i++)
+ write(tmpfile, strout, 8192);
gettimeofday(&elapse_t, NULL);
close(tmpfile);
printf("\topen o_sync, write ");
#ifdef HAVE_FDATASYNC
/* write, fdatasync */
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR)) == -1)
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR)) == -1)
die("can't open /var/tmp/test_fsync.out");
gettimeofday(&start_t, NULL);
- write(tmpfile, strout, 8192);
- fdatasync(tmpfile);
+ for (i = 0; i < loops; i++)
+ {
+ write(tmpfile, strout, 8192);
+ fdatasync(tmpfile);
+ }
gettimeofday(&elapse_t, NULL);
close(tmpfile);
printf("\twrite, fdatasync ");
printf("\n");
/* write, fsync, close */
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR)) == -1)
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR)) == -1)
die("can't open /var/tmp/test_fsync.out");
gettimeofday(&start_t, NULL);
- write(tmpfile, strout, 8192);
- fsync(tmpfile);
+ for (i = 0; i < loops; i++)
+ {
+ write(tmpfile, strout, 8192);
+ fsync(tmpfile);
+ }
gettimeofday(&elapse_t, NULL);
close(tmpfile);
printf("\twrite, fsync, ");
#ifdef OPEN_DATASYNC_FLAG
/* open_dsync, write */
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | O_DSYNC)) == -1)
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR | O_DSYNC)) == -1)
die("can't open /var/tmp/test_fsync.out");
gettimeofday(&start_t, NULL);
- write(tmpfile, strout, 8192);
- write(tmpfile, strout, 8192);
+ for (i = 0; i < loops; i++)
+ {
+ write(tmpfile, strout, 8192);
+ write(tmpfile, strout, 8192);
+ }
gettimeofday(&elapse_t, NULL);
close(tmpfile);
printf("\topen o_dsync, write ");
printf("\n");
/* open_fsync, write */
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | OPEN_SYNC_FLAG)) == -1)
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR | OPEN_SYNC_FLAG)) == -1)
die("can't open /var/tmp/test_fsync.out");
gettimeofday(&start_t, NULL);
- write(tmpfile, strout, 8192);
- write(tmpfile, strout, 8192);
+ for (i = 0; i < loops; i++)
+ {
+ write(tmpfile, strout, 8192);
+ write(tmpfile, strout, 8192);
+ }
gettimeofday(&elapse_t, NULL);
close(tmpfile);
printf("\topen o_sync, write ");
#ifdef HAVE_FDATASYNC
/* write, fdatasync */
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR)) == -1)
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR)) == -1)
die("can't open /var/tmp/test_fsync.out");
gettimeofday(&start_t, NULL);
- write(tmpfile, strout, 8192);
- write(tmpfile, strout, 8192);
- fdatasync(tmpfile);
+ for (i = 0; i < loops; i++)
+ {
+ write(tmpfile, strout, 8192);
+ write(tmpfile, strout, 8192);
+ fdatasync(tmpfile);
+ }
gettimeofday(&elapse_t, NULL);
close(tmpfile);
printf("\twrite, fdatasync ");
printf("\n");
/* write, fsync, close */
- if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR)) == -1)
+ if ((tmpfile = open(FSYNC_FILENAME, O_RDWR)) == -1)
die("can't open /var/tmp/test_fsync.out");
gettimeofday(&start_t, NULL);
- write(tmpfile, strout, 8192);
- write(tmpfile, strout, 8192);
- fsync(tmpfile);
+ for (i = 0; i < loops; i++)
+ {
+ write(tmpfile, strout, 8192);
+ write(tmpfile, strout, 8192);
+ fsync(tmpfile);
+ }
gettimeofday(&elapse_t, NULL);
close(tmpfile);
printf("\twrite, fsync, ");
print_elapse(start_t, elapse_t);
printf("\n");
- unlink("/var/tmp/test_fsync.out");
+ unlink(FSYNC_FILENAME);
return 0;
}
elapse_t.tv_usec += 1000000;
}
- printf("%ld.%06ld", (long) (elapse_t.tv_sec - start_t.tv_sec),
+ printf("%3ld.%06ld", (long) (elapse_t.tv_sec - start_t.tv_sec),
(long) (elapse_t.tv_usec - start_t.tv_usec));
}