Re: Simplifying wal_sync_method

Bruce Momjian <pgman@candle.pha.pa.us>

From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Marko Kreen <marko@l-t.ee>
Cc: PostgreSQL-development <pgsql-hackers@postgreSQL.org>
Date: 2005-08-08T22:02:18Z
Lists: pgsql-hackers
Marko Kreen wrote:
> On Mon, Aug 08, 2005 at 05:38:59PM -0400, Bruce Momjian wrote:
> > Marko Kreen wrote:
> > > On Mon, Aug 08, 2005 at 03:56:39PM -0400, Bruce Momjian wrote:
> > > > Currently, here are the options available for wal_sync_method:
> > > > 
> > > > 	#wal_sync_method = fsync        # the default varies across platforms:
> > > > 	                                # fsync, fdatasync, fsync_writethrough,
> > > > 	                                # open_sync, open_datasync
> > > 
> > > On same topic:
> > > 
> > >   http://archives.postgresql.org/pgsql-general/2005-07/msg00811.php
> > > 
> > > Why does win32 PostgreSQL allow data corruption by default?
> > 
> > It behaves the same on Unix as Win32, and if you have battery-backed
> > cache, you don't need writethrough, so we don't have it as default.  I
> > am going to write a section in the manual for 8.1 about these
> > reliability issues.
> 
> For some reason I don't see "corruped database after crash"
> reports on Unixen.  Why?

They use SCSI or battery-backed RAID cards more often?

> Also, why can't win32 be safe without battery-backed cache?
> I can't see such requirement on other platforms.

If it uses SCSI, it is secure, just like Unix.

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