Jeff Janes wrote:
>
> The following bug has been logged online:
>
> Bug reference: 4965
> Logged by: Jeff Janes
> Email address: jeff.janes@gmail.com
> PostgreSQL version: 8.4.0
> Operating system: Linux
> Description: missing tests in tools/fsync/test_fsync.c
> Details:
>
> In the part that implements "Compare file sync methods with one 8k write",
> the #ifdef OPEN_SYNC_FLAG code
> is nested within the #ifdef OPEN_DATASYNC_FLAG code.
>
> This causes o_sync to be skipped if o_dsync is unavailable, but only for
> this particular section (the section with 2 8k writes doesn't have this
> problem.)
>
> Also, the statement that prints the "Compare file sync methods with one 8k
> write" section title is up in the #ifdef block of a previous section, where
> it might be omitted on systems without an o_sync.
Yea, that C file needed some help. I have applied the attached patch to
CVS HEAD and 8.4.X. Thanks for the report and let me know if you think
this can be improved further.
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ If your life is a hard drive, Christ can be your backup. +
Index: src/tools/fsync/test_fsync.c
===================================================================
RCS file: /cvsroot/pgsql/src/tools/fsync/test_fsync.c,v
retrieving revision 1.23
diff -c -c -r1.23 test_fsync.c
*** src/tools/fsync/test_fsync.c 11 Jun 2009 14:49:15 -0000 1.23
--- src/tools/fsync/test_fsync.c 10 Aug 2009 18:14:36 -0000
***************
*** 30,36 ****
#define FSYNC_FILENAME "/var/tmp/test_fsync.out"
#endif
! #define WRITE_SIZE (16 * 1024)
void die(char *str);
void print_elapse(struct timeval start_t, struct timeval elapse_t);
--- 30,36 ----
#define FSYNC_FILENAME "/var/tmp/test_fsync.out"
#endif
! #define WRITE_SIZE (16 * 1024) /* 16k */
void die(char *str);
void print_elapse(struct timeval start_t, struct timeval elapse_t);
***************
*** 71,76 ****
--- 71,79 ----
buf = (char *) TYPEALIGN(ALIGNOF_XLOG_BUFFER, full_buf);
+ /*
+ * Simple write
+ */
printf("Simple write timing:\n");
/* write only */
gettimeofday(&start_t, NULL);
***************
*** 87,94 ****
print_elapse(start_t, elapse_t);
printf("\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);
--- 90,100 ----
print_elapse(start_t, elapse_t);
printf("\n");
+ /*
+ * Fsync another file descriptor?
+ */
printf("\nCompare fsync times on write() and non-write() descriptor:\n");
! printf("If the times are similar, fsync() can sync data written\non a different descriptor.\n");
/* write, fsync, close */
gettimeofday(&start_t, NULL);
***************
*** 132,137 ****
--- 138,146 ----
print_elapse(start_t, elapse_t);
printf("\n");
+ /*
+ * Compare 1 to 2 writes
+ */
printf("\nCompare one o_sync write to two:\n");
#ifdef OPEN_SYNC_FLAG
***************
*** 148,154 ****
print_elapse(start_t, elapse_t);
printf("\n");
! /* 2*8k o_sync writes */
if ((tmpfile = open(filename, O_RDWR | OPEN_SYNC_FLAG, 0)) == -1)
die("Cannot open output file.");
gettimeofday(&start_t, NULL);
--- 157,163 ----
print_elapse(start_t, elapse_t);
printf("\n");
! /* Two 8k o_sync writes */
if ((tmpfile = open(filename, O_RDWR | OPEN_SYNC_FLAG, 0)) == -1)
die("Cannot open output file.");
gettimeofday(&start_t, NULL);
***************
*** 163,176 ****
close(tmpfile);
printf("\ttwo 8k o_sync writes ");
print_elapse(start_t, elapse_t);
- printf("\n");
-
- printf("\nCompare file sync methods with one 8k write:\n");
#else
printf("\t(o_sync unavailable) ");
#endif
printf("\n");
#ifdef OPEN_DATASYNC_FLAG
/* open_dsync, write */
if ((tmpfile = open(filename, O_RDWR | O_DSYNC, 0)) == -1)
--- 172,187 ----
close(tmpfile);
printf("\ttwo 8k o_sync writes ");
print_elapse(start_t, elapse_t);
#else
printf("\t(o_sync unavailable) ");
#endif
printf("\n");
+ /*
+ * Compare file sync methods with one 8k write
+ */
+ printf("\nCompare file sync methods with one 8k write:\n");
+
#ifdef OPEN_DATASYNC_FLAG
/* open_dsync, write */
if ((tmpfile = open(filename, O_RDWR | O_DSYNC, 0)) == -1)
***************
*** 183,189 ****
--- 194,204 ----
close(tmpfile);
printf("\topen o_dsync, write ");
print_elapse(start_t, elapse_t);
+ #else
+ printf("\t(o_dsync unavailable) ");
+ #endif
printf("\n");
+
#ifdef OPEN_SYNC_FLAG
/* open_fsync, write */
if ((tmpfile = open(filename, O_RDWR | OPEN_SYNC_FLAG, 0)) == -1)
***************
*** 196,204 ****
close(tmpfile);
printf("\topen o_sync, write ");
print_elapse(start_t, elapse_t);
- #endif
#else
! printf("\t(o_dsync unavailable) ");
#endif
printf("\n");
--- 211,218 ----
close(tmpfile);
printf("\topen o_sync, write ");
print_elapse(start_t, elapse_t);
#else
! printf("\t(o_sync unavailable) ");
#endif
printf("\n");
***************
*** 235,245 ****
}
gettimeofday(&elapse_t, NULL);
close(tmpfile);
! printf("\twrite, fsync, ");
print_elapse(start_t, elapse_t);
printf("\n");
! printf("\nCompare file sync methods with 2 8k writes:\n");
#ifdef OPEN_DATASYNC_FLAG
/* open_dsync, write */
--- 249,262 ----
}
gettimeofday(&elapse_t, NULL);
close(tmpfile);
! printf("\twrite, fsync ");
print_elapse(start_t, elapse_t);
printf("\n");
! /*
! * Compare file sync methods with two 8k write
! */
! printf("\nCompare file sync methods with two 8k writes:\n");
#ifdef OPEN_DATASYNC_FLAG
/* open_dsync, write */
***************
*** 318,324 ****
}
gettimeofday(&elapse_t, NULL);
close(tmpfile);
! printf("\twrite, fsync, ");
print_elapse(start_t, elapse_t);
printf("\n");
--- 335,341 ----
}
gettimeofday(&elapse_t, NULL);
close(tmpfile);
! printf("\twrite, fsync ");
print_elapse(start_t, elapse_t);
printf("\n");
