On Mar 1, 2012, at 10:01 AM, Michael Thomas wrote: > The real issue is that gethostbyxxx has been inadequate for a very > long time. Moving it across the kernel boundary solves nothing and > most likely causes even more trouble: what if I want, say, asynchronous > name resolution? What if I want to use SRV records? What if a new DNS > RR comes around -- do i have do recompile the kernel? It's for these > reasons and probably a whole lot more that connect just confuses the > actual issues.
<software-developer-hat-on> My experience is that these calls are expensive and require a lot of work to get a true result. Some systems also have interim caching that happens as well (e.g. NSCD). When building software that did a lot of dns lookups at once, I had to build my own internal cache to maintain performance. Startup costs were expensive, but maintaining it started to space out a bit more and be less of an issue. I ended up caching these entries for 1 hour by default. </hat ?xml-fail> - jared