Re: WIP checksums patch

On Mon, Nov 5, 2012 at 12:19 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:

> On Mon, Oct 29, 2012 at 4:31 PM, Jim Nasby <jim(at)nasby(dot)net> wrote:
> > For whatever it's worth... we (and presumably others) still use londiste
> (or
> > Slony) as our upgrade path, so we could tolerate a cluster-wide setting.
> > We'd just set it when building new clusters via londiste and forget about
> > it.
> >
> > So I'd rather see this get in at a cluster level than not make it at all
> > while we wait for something better.
>
> Yeah. I definitely think that we could shed an enormous amount of
> complexity by deciding that this is, for now, an option that can only
> be selected at initdb time. That would remove approximately 85% of
> everything I've ever disliked about this patch - without, I think,
> precluding the possibility of improving things later.
>
>
I see one thing to be concerned about, there...

I imagine it would not be a totally happy thing if the only way to switch
it on/off was to use Slony or Londiste to replicate into a database with
the opposite setting. (e.g. - This implies that built-in replication may
only replicate into a database with the identical checksum configuration.)

It's not outrageous for it to be a pretty heavyweight operation to switch
polarities, but there's such a thing as too heavy.
--
When confronted by a difficult problem, solve it by reducing it to the
question, "How would the Lone Ranger handle this?"