On Mon, May 6, 2019 at 12:05 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
> > ... I guess you could incur the overhead repeatedly if the relation starts
> > out at 1 block, grows to 4, is vacuumed back down to 1, lather, rinse,
> > repeat, but is that actually realistic?
>
> While I've not studied the patch, I assumed that once a relation has an
> FSM it won't disappear. Making it go away again if the relation gets
> shorter seems both fairly useless and a promising source of bugs.
Right, I think so too. That's not what I as going for, though. I was
trying to discuss a scenario where the relation repeatedly grows,
never reaching the size at which the FSM would be created, and then is
repeatedly truncated again.
--
Robert Haas
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