On Fri, Nov 10, 2006, John Robinson wrote: >>> but then the delay would be the sum of the reply times.
>>> With ONE dnslists condition, it's just the maximum of the single delays.
>> I don't understand what you mean here. What delay are you talking about? >> How does testing on multiple "dnslist" verbs cause any more delay
>> than if Exim were testing multiple entries on a single dnslist verb?
> All the DNS queries could be issued simultaneously, in parallel, instead
> of one after the other.
There's no API for asynchronous DNS lookups in libc or other standard
libraries, though. One would have to either use an external library or
spawn multiple threads/processes.
That seems far too "fancy" for my taste, though. dnslist lookups are
fast and few in numbers enough to justify the simple method of doing
synchronous lookups.
