Re: truncating pg_multixact/members

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> On Sat, Jan 4, 2014 at 12:38 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Keep in mind that 9.3 is still wet behind the ears and many many people
>> haven't adopted it yet. If we do what you're suggesting then we're
>> creating a completely useless inconsistency that will nonetheless affect
>> all those future adopters ... while accomplishing nothing much for those
>> who have already installed 9.3. The latter are not going to have these
>> GUCs in their existing postgresql.conf, true, but there's nothing we can
>> do about that. (Hint: GUC_NOT_IN_SAMPLE doesn't actually *do* anything,
>> other than prevent the variable from being shown by SHOW ALL, which is not
>> exactly helpful here.)

> Well, I guess what I'm really wondering is whether we should refrain
> from patching postgresql.conf.sample in 9.3, even if we add the GUC,
> just because people may have existing configuration files that they've
> already modified, and it could perhaps create confusion.

If we don't update postgresql.conf.sample then we'll just be creating
different confusion. My argument above is that many more people are
likely to be affected in the future by an omission in
postgresql.conf.sample than would be affected now by an inconsistency
between postgresql.conf.sample and their actual conf file.

regards, tom lane