Having just mistakenly performed a large upgrade including powerdns, I'm wondering if there isn't something we can do to minimise the amount of time we stop a service between pre-inst and post-inst. Could we have something like a post-unpack maintainer script or a flag telling dpkg that the package contains a daemon and to minimise the time between the maintainer scripts where possible.

Yes I should read the list archives, but I'm about to go out. Must remember to check when I get back.

Edit:Adeodato Simó pointed out that in most cases daemons should just do a restart in the postinst, unless changing files on disk is a problem. Need to investigate if this is an issue for pdns-server and fix it.