Re: hardware requirements per hits



On Mon, Aug 17, 2009 at 8:50 PM, Alans<batpower83@xxxxxxxxxxx> wrote:
@Matus: let me put it in this way, if I want to create a budget for next
year for example, then I should know what upgrades I need for next year
(estimated needs), and let's assume dns queries increase monthly by x hits,
now, if I know how many hits will make me upgrade cpu and memory then I can
find out my cpu and memory needs for next year, hope this explain to you why
my question is not "usless", at least for me.
I'll be happy if you tell me another way to know my needs for next year.

I'm assuming you already have a running DNS server? In that case I'd
simply gather stats from it. What kind of hardware it currently has,
how much is current CPU and disk load, how many queries per second it
currently serves, etc. Based on that you can have a rough estimate as
to what you'd need to upgrade.

Here are some pointers from my experience though:
- syslog query logging is expensive. NEVER enable it. If you need to
log client queries, log it directly to file instead.
- disk I/O can be a serious bottleneck. If that's the case consider
disable logging.
- BIND would generally work better with faster CPU compared to
multiple CPUs/cores, e.g. 1 x 3GHZ CPU could outperform 2 x 1.5GHz
CPU.
- memory cache can speedup things to a point. Try allocating about
2-4G when you're handing lots of clients.

Those are very general pointers though, YMMV. You might find it easier
to simply add aonther server instead of upgrading.

--
Fajar
.