Re: dnscache performance still applicable today?

Rihad <[email protected]> wrote:
> Let's please not forget where it all started:
> 2009-05-24 18:42:48.254665500 stats 2098047 158736598 190 0
> that 190 "queries that dnscache has received via UDP but not yet
> responded to or dropped".

Some queries, for various reasons, will never be answered.  Typically
this is due to a mistake in the authoritative server's configuration
or records, so there's nothing that can be done about it at the
resolver end.  But dnscache won't give up on those queries until it
fills up its table of 200 in-progress queries, at which point it
throws away the oldest query to make room for the next new one.
That's the only way that the old unanswerable queries will go away, so
once you've accumulated 200 of them, you'll always be close to that.


paul