Re: Sync Rep: First Thoughts on Code

On Tue, 2008-12-09 at 14:42 +0200, Heikki Linnakangas wrote:
> Simon Riggs wrote:
> > For clarity: I don't think its acceptable to have the archiver send
> > files to the archive at the same time as we're streaming data. In normal
> > running we should not duplicate the data paths - its just too much data
> > volume and/or bandwidth.
>
> What if you want to run archiving for backup purposes, and also have a
> standby server?

If we want to include that as an option, yes. If it is "always on" then
no, not everybody wants that.

The best way to implement that is to archive from the standby, not to
send the data twice. By definition the archive is more closely
associated with the standby node than the primary.

Maybe I misunderstood the diagrams? The additional flows to the archive
are actually all optional?

Anyway, I enclose a slightly simplified version of p.6 to allow us to
see the progression of file mode through to streaming mode. This is an
in-my-understanding version.

--
 Simon Riggs           www.2ndQuadrant.com
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