Is asychronous DNS lookup worth keeping at all?

[Eric S. Raymond]

Is asychronous DNS lookup worth keeping at all?  It's costly in code
complexity and dependencies.  I've been thinking about how it affects
performance and I'm now doubting that it is effective  in modern
conditions.

The basic fact here is that if you specify servers or pool hosts by
DNS name, you can't get time corrections before the first DNS lookup
succceeds.  Therefore, asynchronous getaddrinfo can improve time to first
correction only if there is more than one host specified by name.

Nowadays, 99.9% of all NTP installations are configured to do a single
pool name lookup.  Some of the remainder are hand-configured by
sysdamins who care about boot speed enough to specify IP addresses.

The question is: does the remaining tiny fraction of installations
justify the complexity cost?
-- 
		<a href="http://www.catb.org/~esr/">Eric S. Raymond</a>

"The great object is, that every man be armed. [...] 
Every one who is able may have a gun."
        -- Patrick Henry, speech of June 14 1788