Re: [PATCH] Document the order of changing certain settings when using hot-standby servers

On Thu, Apr 13, 2017 at 8:29 AM, Yorick Peterse <yorickpeterse(at)gmail(dot)com> wrote:
> Good point, right now it can give you the idea that applying it to just
> 1 standby (instead of all of them) is good enough, when instead you
> need to apply it to all of them.
>
> Attached is an adjusted version of my changes to better reflect this.

To me, this just seems redundant. The existing documentation already says:

For these parameters,
the value on the standby must
be equal to or greater than the value on the primary. If these parameters
are not set high enough then the standby will refuse to start.

Now you're proposing to add:

If you want to increase these values you
should do so on all standby servers first, before applying the changes to
the primary. If you instead want to decrease these values you should do so
on the primary first, before applying the changes to all standby servers.

But that's just the obvious logical consequence of the existing statement.

If we're going to add this text, I'd move it one sentence earlier and
stick "Therefore, " at the beginning. But it strikes me that it's
just a bet that if we say things twice instead of once, people will
pay more attention -- which is maybe true, but if that's done on a
widespread basis, it will cause the documentation to become bloated.

--
Robert Haas
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