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/*
* test_fsync.c
* tests if fsync can be done from another process than the original write
*/
#include "../../include/pg_config.h"
#include <sys/types.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <sys/time.h>
#include <unistd.h>
/* O_SYNC and O_FSYNC are the same */
#if defined(O_SYNC)
#define OPEN_SYNC_FLAG O_SYNC
#elif defined(O_FSYNC)
#define OPEN_SYNC_FLAG O_FSYNC
#endif
#if defined(OPEN_SYNC_FLAG)
#if defined(O_DSYNC) && (O_DSYNC != OPEN_SYNC_FLAG)
#define OPEN_DATASYNC_FLAG O_DSYNC
#endif
#endif
void die(char *str);
void print_elapse(struct timeval start_t, struct timeval elapse_t);
int main(int argc, char *argv[])
{
struct timeval start_t;
struct timeval elapse_t;
int tmpfile;
char *strout = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
printf("Simple write timing:\n");
/* write only */
gettimeofday(&start_t, NULL);
if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | O_CREAT)) == -1)
die("can't open /var/tmp/test_fsync.out");
write(tmpfile, &strout, 200);
close(tmpfile);
gettimeofday(&elapse_t, NULL);
unlink("/var/tmp/test_fsync.out");
printf("write ");
print_elapse(start_t, elapse_t);
printf("\n\n");
printf("Compare fsync before and after write's close:\n");
/* write, fsync, close */
gettimeofday(&start_t, NULL);
if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | O_CREAT)) == -1)
die("can't open /var/tmp/test_fsync.out");
write(tmpfile, &strout, 200);
fsync(tmpfile);
close(tmpfile);
gettimeofday(&elapse_t, NULL);
unlink("/var/tmp/test_fsync.out");
printf("write, fsync, close ");
print_elapse(start_t, elapse_t);
printf("\n");
/* write, close, fsync */
gettimeofday(&start_t, NULL);
if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | O_CREAT)) == -1)
die("can't open /var/tmp/test_fsync.out");
write(tmpfile, &strout, 200);
close(tmpfile);
/* reopen file */
if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | O_CREAT)) == -1)
die("can't open /var/tmp/test_fsync.out");
fsync(tmpfile);
close(tmpfile);
gettimeofday(&elapse_t, NULL);
unlink("/var/tmp/test_fsync.out");
printf("write, close, fsync ");
print_elapse(start_t, elapse_t);
printf("\n");
printf("\nTest file sync methods\n");
#ifdef OPEN_DATASYNC_FLAG
/* open_dsync, write */
gettimeofday(&start_t, NULL);
if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | O_CREAT | O_DSYNC)) == -1)
die("can't open /var/tmp/test_fsync.out");
write(tmpfile, &strout, 200);
close(tmpfile);
gettimeofday(&elapse_t, NULL);
unlink("/var/tmp/test_fsync.out");
printf("open o_dsync, write ");
print_elapse(start_t, elapse_t);
printf("\n");
#endif
/* open_fsync, write */
gettimeofday(&start_t, NULL);
if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | O_CREAT | OPEN_SYNC_FLAG)) == -1)
die("can't open /var/tmp/test_fsync.out");
write(tmpfile, &strout, 200);
close(tmpfile);
gettimeofday(&elapse_t, NULL);
unlink("/var/tmp/test_fsync.out");
printf("open o_fsync, write ");
print_elapse(start_t, elapse_t);
printf("\n");
#ifdef HAVE_FDATASYNC
/* write, fdatasync */
gettimeofday(&start_t, NULL);
if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | O_CREAT)) == -1)
die("can't open /var/tmp/test_fsync.out");
write(tmpfile, &strout, 200);
fdatasync(tmpfile);
close(tmpfile);
gettimeofday(&elapse_t, NULL);
unlink("/var/tmp/test_fsync.out");
printf("write, fdatasync ");
print_elapse(start_t, elapse_t);
printf("\n");
#endif
/* write, fsync, close */
gettimeofday(&start_t, NULL);
if ((tmpfile = open("/var/tmp/test_fsync.out", O_RDWR | O_CREAT)) == -1)
die("can't open /var/tmp/test_fsync.out");
write(tmpfile, &strout, 200);
fsync(tmpfile);
close(tmpfile);
gettimeofday(&elapse_t, NULL);
unlink("/var/tmp/test_fsync.out");
printf("write, fsync, ");
print_elapse(start_t, elapse_t);
printf("\n");
return 0;
}
void print_elapse(struct timeval start_t, struct timeval elapse_t)
{
if (elapse_t.tv_usec < start_t.tv_usec)
{
elapse_t.tv_sec--;
elapse_t.tv_usec += 1000000;
}
printf("%ld.%06ld", (long) (elapse_t.tv_sec - start_t.tv_sec),
(long) (elapse_t.tv_usec - start_t.tv_usec));
}
void die(char *str)
{
fprintf(stderr, "%s", str);
exit(1);
}
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