Re: dns avg service time

Adalto Silva Correia Filho wrote:
>
> Dear Friends,
>
> My dnsserver avg service time is about 2302 msec!
>
> I'm using 10 dnschildren and the last one is idle. I have an IBM
> J40 running AIX 4.1.2. This box has squid 1.1.20. I use another machine
> as the DNS Server.
>
> What could I do to low this avg service time? Is there any
> improvements in Squid 2.0 relative to this specific topic?

First thing you can do is try increasing the size of your ipcache and
fqdn cache in the config. Double 'em. Triple 'em. Add a zero. That'll
hold you some until you can address the _real_ problem, which is that
name lookups on the DNS machine aren't completing in a timely fashion.

Off the top of my pointy little head, I see a couple possibilities:

1) Your DNS box is too busy. Point to a less heavily loaded DNS server.
2) Your DNS box is referring requests to an overloaded server, or
through a poor link. In the former case, specify more forwarders for the
DNS box. In the latter case, pray to the net.gods for more bandwidth *g*

I _have_ had good results in the first case (overloaded DNS box) by
putting a copy of bind/named on the squid box itself. That's one less
hop to deal with. In this case you are trading off CPU cycles for a
saving of a handful of milliseconds. Not surprisingly, if you can spare
the CPU time, this can be quite effective.

D
Received on Wed Mar 03 1999 - 10:58:21 MST