Index: test_fsync.c
===================================================================
RCS file: /home/jjanes/pgrepo/pgsql/src/tools/fsync/test_fsync.c,v
retrieving revision 1.24
diff -c -r1.24 test_fsync.c
*** test_fsync.c	10 Aug 2009 18:19:06 -0000	1.24
--- test_fsync.c	13 Sep 2009 17:29:27 -0000
***************
*** 31,36 ****
--- 31,37 ----
  #endif
  
  #define WRITE_SIZE	(16 * 1024) /* 16k */
+ #define REWIND_FILE	if (i%1020 == 1019 && (-1 == lseek(tmpfile,0,SEEK_SET))) die ("Cannot lseek.");
  
  void		die(char *str);
  void		print_elapse(struct timeval start_t, struct timeval elapse_t);
***************
*** 148,156 ****
  	if ((tmpfile = open(filename, O_RDWR | OPEN_SYNC_FLAG, 0)) == -1)
  		die("Cannot open output file.");
  	gettimeofday(&start_t, NULL);
! 	for (i = 0; i < loops; i++)
  		if (write(tmpfile, buf, WRITE_SIZE) != WRITE_SIZE)
  			die("write failed");
  	gettimeofday(&elapse_t, NULL);
  	close(tmpfile);
  	printf("\tone 16k o_sync write   ");
--- 149,160 ----
  	if ((tmpfile = open(filename, O_RDWR | OPEN_SYNC_FLAG, 0)) == -1)
  		die("Cannot open output file.");
  	gettimeofday(&start_t, NULL);
! 	for (i = 0; i < loops; i++) 
! 	{
! 		REWIND_FILE;
  		if (write(tmpfile, buf, WRITE_SIZE) != WRITE_SIZE)
  			die("write failed");
+ 	};
  	gettimeofday(&elapse_t, NULL);
  	close(tmpfile);
  	printf("\tone 16k o_sync write   ");
***************
*** 163,168 ****
--- 167,173 ----
  	gettimeofday(&start_t, NULL);
  	for (i = 0; i < loops; i++)
  	{
+ 		REWIND_FILE;
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
  			die("write failed");
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
***************
*** 188,195 ****
--- 193,203 ----
  		die("Cannot open output file.");
  	gettimeofday(&start_t, NULL);
  	for (i = 0; i < loops; i++)
+ 	{
+ 		REWIND_FILE;
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
  			die("write failed");
+ 	}
  	gettimeofday(&elapse_t, NULL);
  	close(tmpfile);
  	printf("\topen o_dsync, write    ");
***************
*** 205,212 ****
--- 213,223 ----
  		die("Cannot open output file.");
  	gettimeofday(&start_t, NULL);
  	for (i = 0; i < loops; i++)
+ 	{
+ 		REWIND_FILE;
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
  			die("write failed");
+ 	}
  	gettimeofday(&elapse_t, NULL);
  	close(tmpfile);
  	printf("\topen o_sync, write     ");
***************
*** 223,228 ****
--- 234,240 ----
  	gettimeofday(&start_t, NULL);
  	for (i = 0; i < loops; i++)
  	{
+ 		REWIND_FILE;
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
  			die("write failed");
  		fdatasync(tmpfile);
***************
*** 242,247 ****
--- 254,260 ----
  	gettimeofday(&start_t, NULL);
  	for (i = 0; i < loops; i++)
  	{
+ 		REWIND_FILE;
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
  			die("write failed");
  		if (fsync(tmpfile) != 0)
***************
*** 265,270 ****
--- 278,284 ----
  	gettimeofday(&start_t, NULL);
  	for (i = 0; i < loops; i++)
  	{
+ 		REWIND_FILE;
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
  			die("write failed");
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
***************
*** 286,291 ****
--- 300,306 ----
  	gettimeofday(&start_t, NULL);
  	for (i = 0; i < loops; i++)
  	{
+ 		REWIND_FILE;
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
  			die("write failed");
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
***************
*** 305,310 ****
--- 320,326 ----
  	gettimeofday(&start_t, NULL);
  	for (i = 0; i < loops; i++)
  	{
+ 		REWIND_FILE;
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
  			die("write failed");
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
***************
*** 326,331 ****
--- 342,348 ----
  	gettimeofday(&start_t, NULL);
  	for (i = 0; i < loops; i++)
  	{
+ 		REWIND_FILE;
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
  			die("write failed");
  		if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)