resolving from loopback is much smooth?

[Graham Clinch]

Hi Eric,

> I run bind dns server 9.9 now with around 3000query/s.  I recently
> upgrade our server to Fujitsu M10-1 Solaris 10 with bind9.10.
> I feel that the server serving bind is not as fast as old one in intel
> solaris which was more than 8 years ago.  I tried a few test
> and found that dig @localhost is much more smooth thatn dig @IP the zone
> at the machine.

Which specific version of 9.10 are you running?  There is a reported
issue with prefetch in versions before 9.10.4 (and prefetch is enabled
by default in 9.10):

https://kb.isc.org/article/AA-01315/0/prefetch-performance-in-BIND-9.10.html

We saw similar problems that only affected the service IPs (when they
were running 9.10.3) and on reviewing netstat saw large receive queues
on the affected listeners.

Disabling prefetch as discussed in the document helped us.

(we've since moved to 9.10.4 but haven't yet re-enabled prefetch).

Graham