Re: host name support in pg_hba.conf

On Mon, Aug 09, 2010 at 03:25:23PM -0400, Tom Lane wrote:
> Peter Eisentraut <peter_e(at)gmx(dot)net> writes:
> > Here is a patch for host name support in pg_hba.conf.
>
> My recollection is that the previous discussions got stuck on the cost
> of doing DNS lookups for every connect; and the obvious solution of
> trying to cache the names was shot down on the basis of not knowing when
> to flush the cache. Have you decided that people who want this feature
> will just have to pay that cost? If so, I think the documentation needs
> to be a bit more explicit about names being more expensive than IP
> addresses in pg_hba.conf.

I am also a bit scared of the startup cost for each connection.

In which order are things evaluated? What if I only include IP
addresses in my pg_hba, will it still cost me a DNS lookup or
two?

Kind regards,
Kristian.

--
Kristian Larsson KLL-RIPE
+46 704 264511 kll(at)spritelink(dot)net