Robert Haas <robertmh...@gmail.com> writes: > On Wed, Jul 19, 2017 at 1:35 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: >> Alternatively, we could turn the origin point for abstime into >> pg_control field, and regard changing it as a reason for a database >> not being pg_upgrade'able unless it lacks any abstime columns.
> I would be OK with that, too, but is there any danger that we're going > to grow pg_control to a size where reads and writes can no longer be > assumed atomic, if we keep adding things? Hm. Currently sizeof(struct ControlFileData) = 296, at least on my machine. Letting it grow past 512 would be problematic. It's hard to see getting to that any time soon, though; we don't add fields there often. Note that I'm not seriously pushing for this solution. I'm just trying to make sure that we've considered all the reasonable options. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers