Re: Is it time to kill support for very old servers?

Andres Freund <andres(at)anarazel(dot)de> writes:
> Re-upping this topic.

> On 2016-10-07 10:06:07 -0400, Tom Lane wrote:
>> In the same line, maybe we should kill libpq's support for V2 protocol
>> (which would make the cutoff 7.4). And maybe the server's support too,
>> though that wouldn't save very much code. The argument for cutting this
>> isn't so much that we would remove lots of code as that we're removing
>> code that never gets tested, at least not by us.

> I'd like to do this in the not too far away future for at least the
> backend. There's enough not particularly pretty code to deal with v2
> that that'd be worthwhile.

Hm, I don't recall that there's very much on the server side that could be
saved --- what's incurring your ire, exactly?

>> One small problem with cutting libpq's V2 support is that the server's
>> report_fork_failure_to_client() function still sends a V2-style message.

> We should really fix that so it reports the error as a v3 message,
> independent of ripping out libpq-fe support for v2.

It might be reasonable to do that, but libpq would have to be prepared
for the other case for many years to come :-(

The real problem in this area, to my mind, is that we're not testing that
code --- either end of it --- in any systematic way. If it's broken it
could take us quite a while to notice.

regards, tom lane