[bind10-dev] Resolver - address database requirements

[Evan Hunt]

> Rob's suggestion of a lock-less
> per-thread LRU queue is interesting though, although I guess there is
> more overhead involved in removing an entry when the TTL is reached, as
> the entry could be in more than one of these queues at the same time.

Why bother removing an entry when the TTL is reached?  If it's looked up
and its TTL turns out to have expired, then refresh the entry; otherwise,
no need to worry about it.  If it's not being regularly accessed,
eventually it'll fall off the bottom of the LRU queue anyway.

                                        eh