Re: Our naming of wait events is a disaster.

On Tue, 12 May 2020 at 21:00, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> Simon Riggs <simon(at)2ndquadrant(dot)com> writes:
> > On Tue, 12 May 2020 at 19:11, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >> Anyway, I was just throwing this idea out to see if there would be
> >> howls of "you can't rename anything" anguish. Since there haven't
> >> been so far, I'll spend a bit more time and try to create a concrete
> >> list of possible changes.
>
> > If we add in extensions and lwlocks, will they show up as well?
>
> Yeah, I was just looking into that. Part of the reason for the
> inconsistency is that we've exposed names that are passed to,
> eg, SimpleLruInit that previously were strictly internal debugging
> identifiers, so that approximately zero thought was put into them.
>
> We're going to have to document SimpleLruInit and similar functions
> along the lines of "The name you give here will be user-visible as
> a wait event. Choose it with an eye to consistency with existing
> wait event names, and add it to the user-facing documentation."
> But that requirement isn't something I just invented, it was
> effectively created by whoever implemented things this way.
>
> Said user-facing documentation largely fails to explain that the
> set of wait events can be enlarged by extensions; that needs to
> be fixed, too.
>
> There isn't a lot we can do to force extensions to pick consistent
> names, but on the other hand we won't be documenting such names
> anyway, so for my immediate purposes it doesn't matter ;-)
>

I think we need to plan the namespace with extensions in mind.

There are now dozens; some of them even help you view wait events...

We don't want the equivalent of the Dewey decimal system: 300 categories of
Exaggeration and one small corner for Science.

--
Simon Riggs http://www.2ndQuadrant.com/
<http://www.2ndquadrant.com/>
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