Memory Usage

Unbound
1

Hi,

A few weeks ago, we put Unbound in as a caching internal DNS server and we started graphing stats in Cacti within the next couple of days. Over the last two weeks, it appears that the memory usage is creeping up for these metrics:

Metric Min Max

RRset cache memory 6.9 M 56.38 M

Messages cache memory 6.0 M 59.79 M

Validator memory key cache 703.35 K 5.51 M

All of these have moved up little just about every day.

Thanks,

Paul

2

Zitat von Paul Taylor <PaulTaylor@winn-dixie.com>:

Hi,

                A few weeks ago, we put Unbound in as a caching internal
DNS server and we started graphing stats in Cacti within the next couple
of days. Over the last two weeks, it appears that the memory usage is
creeping up for these metrics:

Metric Min
Max
RRset cache memory 6.9 M 56.38 M
Messages cache memory 6.0 M 59.79 M
Validator memory key cache 703.35 K 5.51 M

All of these have moved up little just about every day.

Hello

Sorry, i do not understand your question. What limits do you have in unbound.conf? Is it simply the fact that memory usage is raising you are worried about, or unbound not working within configured limits?

Regards

andreas

3

Sorry, I think I was in a bit of a hurry when I wrote this and didn't
complete my thought.

I can't say what my settings are without digging into the config
file(I'm travelling at the moment), but I wouldn't generally expect
memory use to continuously increase. The number of devices using this
DNS server isn't really changing and my cache timeout is only 10
minutes. So, if the number of users (and presumably the number of
queries) aren't increasing, and the cache timeout is so low that the
overall cache size shouldn't be continuously growing, why would the
memory usage keep going up?

Anyone else out there monitoring their Unbound usage with Cacti? How
does your memory usage look?

Thanks,
Paul

4

Hi Paul,

AFAIK, Unbound does not free its cache memory during normal operation.
It just adds to it until the cache(s) reach(es) the specified limit,
then it makes room for more by getting rid of some old cache entries. If
an expired cache entry is found it is just ignored, and replaced when
new data is inserted into the cache.

Hope this helps,

Jan.