Re: max_standby_delay considered harmful

Andres Freund <andres(at)anarazel(dot)de> writes:
> On Sunday 09 May 2010 01:34:18 Bruce Momjian wrote:
>> I think everyone agrees the current code is unusable, per Heikki's
>> comment about a WAL file arriving after a period of no WAL activity, and
>> look how long it took our group to even understand why that fails so
>> badly.

> To be honest its not *that* hard to simply make sure generating wal regularly
> to combat that. While it surely aint a nice workaround its not much of a
> problem either.

Well, that's dumping a kluge onto users; but really that isn't the
point. What we have here is a badly designed and badly implemented
feature, and we need to not ship it like this so as to not
institutionalize a bad design.

I like the proposal of a boolean because it provides only the minimal
feature set of two cases that are both clearly needed and easily
implementable. Whatever we do later is certain to provide a superset
of those two cases. If we do something else (and that includes my own
proposal of a straight lock timeout), we'll be implementing something
we might wish to take back later. Taking out features after they've
been in a release is very hard, even if we realize they're badly
designed.

regards, tom lane