Re: GUC with units, details

Peter Eisentraut <peter_e(at)gmx(dot)net> writes:
> Tom Lane wrote:
>> Peter's not said exactly how he plans to deal with
>> this, but I suppose it'll round off one way or the other ...

> It'll get truncated by integer division. I wouldn't mind if someone
> proposed a patch to create a warning or error in this case, but I
> wanted to keep the initial version simple.

I'd recommend against that. Apple recently changed OS X so that
it rejects SHMMAX settings that aren't an exact multiple of
something-or-other, and I've found that to be a *serious* PITA.
Of course part of the problem is that there's no helpful message,
but it's still a big loss from a usability standpoint, and quite
unnecessary (every other Unix seems willing to round off...)

One thought is that maybe we should round up not down? I'm having
a hard time making a specific case either way, though.

regards, tom lane