Memory usage BIND 9.2.1

[Simon Waters]

Dave Ellenberger wrote:
> 
> First sorry for not reading the whole BIND manual ;-)

I mostly only go to chapter 6 and search these days anyway ;)

> Is there a way to tell BIND 9.2.1 to free up memory or only use a fixed
> amount of memory? 

A quick search of chapter 6 :)

You could try forcing the early expiry of data.

max-cache-ttl
max-ncache-ttl

Might give you a clearer idea what is causing the growth.

I think max-cache-size is now implemented as well, but that is
the topic of another thread.

You could dump cache and perhaps get an idea if you really have
that much useful data? Or at least spot the network scan utility
that is looking up IP addresses in the DNS sequentially ;)

> Why does BIND 9.2.1 use so much more RAM than 8.<latestversion>?

Haven't messed with 8 for ages, but I think 9 honours negative
cache time to live (for 3 hours anyway), so if you have some
badly configured clients, or things that are overly chatty,
you'd be caching the nonexistence for 3 hours instead of 10
minutes (the old limit). If so you might be seeing performance
gains in clients if you can stay out of swap, as the nonexistent
names are rejected quicker.

Anyone know how many bytes per record BIND 8 used?