Re: pgbench bug / limitation

Andres Freund <andres(at)anarazel(dot)de> writes:
> I'm fairly sure one can easily scale to large numbers of sockets on
> windows by using completion based APIs, but that doesn't seem like a
> realistic thing to use for pgbench anytime soon.

Agreed. Seems like the best answer is to get in bed with the Windows
representation of fd_set, since we cannot avoid knowing that it is
different from other platforms' versions. I suggest that we might as
well get all the way in and dodge the FD_SETSIZE limitation altogether,
as per the attached utterly-untested draft patch.

A remaining problem with this is that in theory, repeatedly applying
socket_has_input() after the wait could also be O(N^2) (unless FD_ISSET
is way smarter than I suspect it is). In practice, that's probably not
a huge problem since there would normally be only a few FDs in the
result fd_set. Still, I'd rather see us get out from under select()
altogether on Windows ... but maybe they *don't* have a better API
anywhere. In any case, this should be a good bit better than what we
have now.

regards, tom lane