From 576477e73c4a9cb32c7471c1cec354fd5328140e Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Wed, 8 Dec 2010 20:01:09 -0500 Subject: Force default wal_sync_method to be fdatasync on Linux. Recent versions of the Linux system header files cause xlogdefs.h to believe that open_datasync should be the default sync method, whereas formerly fdatasync was the default on Linux. open_datasync is a bad choice, first because it doesn't actually outperform fdatasync (in fact the reverse), and second because we try to use O_DIRECT with it, causing failures on certain filesystems (e.g., ext4 with data=journal option). This part of the patch is largely per a proposal from Marti Raudsepp. More extensive changes are likely to follow in HEAD, but this is as much change as we want to back-patch. Also clean up confusing code and incorrect documentation surrounding the fsync_writethrough option. Those changes shouldn't result in any actual behavioral change, but I chose to back-patch them anyway to keep the branches looking similar in this area. In 9.0 and HEAD, also do some copy-editing on the WAL Reliability documentation section. Back-patch to all supported branches, since any of them might get used on modern Linux versions. --- src/backend/utils/misc/postgresql.conf.sample | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/backend/utils/misc/postgresql.conf.sample') diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index 80ee04d30a9..f436b834680 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -157,7 +157,7 @@ #wal_sync_method = fsync # the default is the first option # supported by the operating system: # open_datasync - # fdatasync + # fdatasync (default on Linux) # fsync # fsync_writethrough # open_sync -- cgit v1.2.3