Re: allow online change primary_conninfo

Now, would anyone be too upset if I push these in this other order?  I
realized that the reason the tests broke after Sergei's patch is that
recovery/t/001_stream_rep.pl's get_slot_xmins() is broken for temp
walreceiver slots, since it's using the non-temp name it tries to give
to the slot, rather than the temp name under which it is actually
created.  The workaround proposed by 0002 is to edit standby_1's config
to set walreceiver's slot to be non-temp.

Thanks to Justin Pryzby for offlist typo corrections.

The reason is that I think I would like to get Sergei's patch pushed
right away (0001+0002, as a single commit); but that I think there's
more to attack in the walreceiver temp slot code than 0003 here, and I
don't want to delay the new feature any longer while I figure out the
fix for that.


(The thing is: if I specify primary_slot_name in the config, why is the
temp walreceiver slot code not obeying that name?  I think walreceiver
should create a temp slot, sure, but using the given name rather than
coming up with a random name.)

(The other reason is that I would like to push one patch to fix
walreceiver tmp slot rather than two, setting the thing first this way
and then the opposite way.)

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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