postgres.git / summary / log / commit / refs

commit    c6b1724c672f7875f1eb58f22248ce1d2dfe4fa7
Author:   Bruce Momjian <bruce@momjian.us>
Date:     Fri Jul 29 03:25:53 2005 +0000
First released in: 8.1.0

    Update O_DIRECT comment.


 src/backend/access/transam/xlog.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index fc9264cfcd9..3f393eb10de 100644
--- 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 1.211 2005/07/29 03:22:33 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.212 2005/07/29 03:25:53 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -54,6 +54,8 @@
  *	with fsync(), but because skipping the kernel buffer forces writes out
  *	quickly, it seems best just to use it for O_SYNC.  It is hard to imagine
  *	how fsync() could be a win for O_DIRECT compared to O_SYNC and O_DIRECT.
+ *	Also, O_DIRECT is never enough to force data to the drives, it merely
+ *	tries to bypass the kernel cache, so we still need O_SYNC or fsync().
  */
 #ifdef O_DIRECT
 #define PG_O_DIRECT				O_DIRECT


[parent: 5b63e7b467fd]