Re: Simplifying wal_sync_method

On Tue, Aug 09, 2005 at 10:02:44AM +0200, Magnus Hagander wrote:
> > > 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
>
> Correction, if you have bbwc, you *should not* have writethrough. Not
> only do you not need it, enabling it will drastically lower performance.

So what? User should read docs how to get good performance.

> > Also, why can't win32 be safe without battery-backed cache?
> > I can't see such requirement on other platforms.
>
> It can, you just need to learn how to configure your system. There are
> two different options to make it safe on win32 without battery backed
> cache:

I personally do not use PostgreSQL in win32 (yet - this may
change). I just felt the pain of a guy who tried...

> in traditional windows style *a single checkbox* in the harddisk
> configuration.
> (Granted, you need a modern windows for that. On older windows it's a
> registry key)

I think PostgreSQL should reliable by default.

Now with the Windows port there are lot of people who just try it out
on regular desktop machine.

With point-n-click installer there's no need to read docs and
after experiencing the unreliability they won't take it as
serious database.

> I have some code floating in my tree to issue a WARNING on startup if
> write cache is enabled and postgresql is not using writethrough. It's
> not quite ready yet, but if such a thing would be accepted post
> feature-freeze I can have it finished in good time before 8.1. It would
> be quite simple (looking at just the main data directory for example,
> ignoring tablespaces), but if you're dealing with complex installations
> you'd better have a clue about how windows works anyway...

Hey, thats a good idea, irrespective whether the default changes or not.

I think if it's just couple of checks and then printf, it should
not meet much resistance.

--
marko