Re: Replication and PITR

[Jim Nasby <decibel(at)decibel(dot)org>]

On Sep 22, 2006, at 1:34 PM, Jeff Davis wrote:
> On Fri, 2006-09-22 at 07:47 +0200, Bo Lorentsen wrote:
> > Bill Moran wrote:
> > > - No reliability.  On slow days, WAL logs could take a long time to
> > >   rotate, so small but important transactions might not be  
> > > replicated
> > >   for a long time.
> > So it is all right for backup but for replication it could end up  
> > laking
> > too much behind, and a fail over could be hours behind.
> >
> > So PITR can be used, but one of the cons is the unpredictable  
> > delay of
> > data. I thought one of the ideas behind the PITR system was to get
> > rather reason backups of data ...
>
> 8.2 will fix this. You can send the WALs periodically even if they're
> not full. In general, PITR will be substantially improved in 8.2  
> (thanks
> Simon!).

You can work around it right now, too; you just need an external  
process that will find the active WAL file and periodically copy it  
to the backup. I'm pretty sure there's info in the archives about the  
details of setting this up, and there's also the PITRHA project on  
pgFoundry.
--
Jim Nasby                                            jim(at)nasby(dot)net
EnterpriseDB      http://enterprisedb.com      512.569.9461 (cell)