Re: RAID0 and pg_xlog

On Fri, 2005-09-09 at 18:54, Jim C. Nasby wrote:
> On Fri, Sep 09, 2005 at 06:20:21PM -0500, Scott Marlowe wrote:
> > > pgpool is a connection pool; it has (almost) nothing to do with
> > > replication. It certainly doesn't work to provide any kind of data
> > > security on a RAID0 setup.
> > >
> > > I'm not arguing against anything people have suggested, only pointing
> > > out that if you're using RAID0 your data is not safe against a drive
> > > failure, except possible using pgcluster (some would argue that
> > > statement-based replication isn't as reliable as log-based).
> >
> > Um. No. It has a synchronous replication mode, which I've used, and it
> > works quite well.
> >
> > Look it up, it's pretty cool. Writes to both pg machines synchronously,
> > reads from them load balanced. Of course, there are some limits imposed
> > by this methodology, re: things like random() and such.
> >
> > Now, if you're arguing against statement based replication, that I can
> > understand. but pgpool can definitely do two box sync replication.
>
> Oh, I didn't realize that. Though I have to wonder why they duplicated
> what pgcluster provides...

I doubt it's as good as pgcluster. It's simple dual machine sync
replication. I think it was a case of being 95% there when the pooling
part was done, so why not just toss in replication for good measure.