Change Win32 O_SYNC method to O_DSYNC because that is what the method

currently does.  This is now the default Win32 wal sync method because
we perfer o_datasync to fsync.

Also, change Win32 fsync to a new wal sync method called
fsync_writethrough because that is the behavior of _commit, which is
what is used for fsync on Win32.

Backpatch to 8.0.X.

diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml
index 33c661dd5cb0b00998a70890f1f8bcb60056a915..408418ee33a62f89204ea4cd803576e944ba5dc0 100644 (file)
--- a/doc/src/sgml/runtime.sgml
+++ b/doc/src/sgml/runtime.sgml
@@ -1,5 +1,5 @@
 
 
 
@@ -1587,6 +1587,7 @@ SET ENABLE_SEQSCAN TO OFF;
         values are
         fsync (call fsync() at each commit),
         fdatasync (call fdatasync() at each commit),
+        fsync_writethrough (call _commit() at each commit on Windows),
         open_sync (write WAL files with open() option O_SYNC), and
         open_datasync (write WAL files with open() option O_DSYNC).
         Not all of these choices are available on all platforms.

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 1a5772798b786723df43cab5002af1a2a90c49f0..6bc5b78780c024ff8edac96d163b9915cf3dabc9 100644 (file)
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.181 2005/02/12 23:53:37 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.182 2005/03/24 04:36:17 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -63,8 +63,13 @@
 #endif
 #endif
 
+#if defined(O_DSYNC)
 #if defined(OPEN_SYNC_FLAG)
-#if defined(O_DSYNC) && (O_DSYNC != OPEN_SYNC_FLAG)
+#if O_DSYNC != OPEN_SYNC_FLAG
+#define OPEN_DATASYNC_FLAG   O_DSYNC
+#endif
+#else /* !defined(OPEN_SYNC_FLAG) */
+/* Win32 only has O_DSYNC */
 #define OPEN_DATASYNC_FLAG   O_DSYNC
 #endif
 #endif
@@ -79,7 +84,11 @@
 #define DEFAULT_SYNC_METHOD          SYNC_METHOD_FDATASYNC
 #define DEFAULT_SYNC_FLAGBIT     0
 #else
+#ifndef FSYNC_IS_WRITE_THROUGH
 #define DEFAULT_SYNC_METHOD_STR   "fsync"
+#else
+#define DEFAULT_SYNC_METHOD_STR   "fsync_writethrough"
+#endif
 #define DEFAULT_SYNC_METHOD          SYNC_METHOD_FSYNC
 #define DEFAULT_SYNC_FLAGBIT     0
 #endif
@@ -5154,7 +5163,12 @@ assign_xlog_sync_method(const char *method, bool doit, GucSource source)
    int         new_sync_method;
    int         new_sync_bit;
 
+#ifndef FSYNC_IS_WRITE_THROUGH
    if (pg_strcasecmp(method, "fsync") == 0)
+#else
+   /* Win32 fsync() == _commit(0, which writes through a write cache */
+   if (pg_strcasecmp(method, "fsync_writethrough") == 0)
+#endif
    {
        new_sync_method = SYNC_METHOD_FSYNC;
        new_sync_bit = 0;

diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index b68cd2f8cf9797f9e736f33c015c7a937c2e03e6..113021fd79f175b87cf154b18d9f286e11923e37 100644 (file)
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -114,7 +114,8 @@
 
 #fsync = true          # turns forced synchronization on or off
 #wal_sync_method = fsync   # the default varies across platforms:
-               # fsync, fdatasync, open_sync, or open_datasync
+               # fsync, fdatasync, fsync_writethrough,
+               # open_sync, open_datasync
 #wal_buffers = 8       # min 4, 8KB each
 #commit_delay = 0      # range 0-100000, in microseconds
 #commit_siblings = 5       # range 1-1000

diff --git a/src/include/port/win32.h b/src/include/port/win32.h
index c3c7da737bca64d00f73b1ab3c5680837057a529..de2483add01dbc781d8ce961753fe31bf81052ba 100644 (file)
--- a/src/include/port/win32.h
+++ b/src/include/port/win32.h
@@ -1,4 +1,4 @@
-/* $PostgreSQL: pgsql/src/include/port/win32.h,v 1.43 2005/02/27 00:53:29 momjian Exp $ */
+/* $PostgreSQL: pgsql/src/include/port/win32.h,v 1.44 2005/03/24 04:36:19 momjian Exp $ */
 
 /* undefine and redefine after #include */
 #undef mkdir
@@ -17,6 +17,7 @@
 
 
 #define fsync(a)   _commit(a)
+#define FSYNC_IS_WRITE_THROUGH
 #define ftruncate(a,b) chsize(a,b)
 
 #define USES_WINSOCK
@@ -189,7 +190,7 @@ typedef int pid_t;
  * to ensure that we don't collide with a future definition. It means
  * we cannot use _O_NOINHERIT ourselves.
  */
-#define O_SYNC 0x0080
+#define O_DSYNC 0x0080
 
 /*
  * Supplement to .

diff --git a/src/port/open.c b/src/port/open.c
index cd17f4164f470c436a094d39ff5652180ebd1747..6e1d37d3cbae9f7e554067b3d945c1ef47c1c5d1 100644 (file)
--- a/src/port/open.c
+++ b/src/port/open.c
@@ -6,7 +6,7 @@
  *
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/port/open.c,v 1.8 2005/02/27 00:53:29 momjian Exp $
+ * $PostgreSQL: pgsql/src/port/open.c,v 1.9 2005/03/24 04:36:20 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -63,7 +63,7 @@ win32_open(const char *fileName, int fileFlags,...)
    /* Check that we can handle the request */
    assert((fileFlags & ((O_RDONLY | O_WRONLY | O_RDWR) | O_APPEND |
                         (O_RANDOM | O_SEQUENTIAL | O_TEMPORARY) |
-                        _O_SHORT_LIVED | O_SYNC |
+                        _O_SHORT_LIVED | O_DSYNC |
      (O_CREAT | O_TRUNC | O_EXCL) | (O_TEXT | O_BINARY))) == fileFlags);
 
    sa.nLength = sizeof(sa);
@@ -83,7 +83,7 @@ win32_open(const char *fileName, int fileFlags,...)
           ((fileFlags & O_SEQUENTIAL) ? FILE_FLAG_SEQUENTIAL_SCAN : 0) |
          ((fileFlags & _O_SHORT_LIVED) ? FILE_ATTRIBUTE_TEMPORARY : 0) |
             ((fileFlags & O_TEMPORARY) ? FILE_FLAG_DELETE_ON_CLOSE : 0)|
-                   ((fileFlags & O_SYNC) ? FILE_FLAG_WRITE_THROUGH : 0),
+                   ((fileFlags & O_DSYNC) ? FILE_FLAG_WRITE_THROUGH : 0),
                        NULL)) == INVALID_HANDLE_VALUE)
    {
        switch (GetLastError())