Deadwood at OpenWRT

[Sam Trenholme]

>> I’m very curious how well Deadwood works on an embedded OpenWRT host.
>>
> I just used the host.txt Juergen Daubert posted a few days ago and ran
> it from a client. I am connected on a cable connection with a latency of
> 10ms to my upstream DNS Server.
>
> It took 0m57.597s to finish, before the MaraDNS upstream server cached
> the results and 0m13.621s after the upstream MaraDNS cached it.

Nice, and very fast.  Is Deadwood able to do its own recursion with
reasonable performance on an embedded OpenWRT host?  I know that, on
Windows, Deadwood needs three or four megs of memory to work as a
fully recursive nameserver with 1024 entries in the cache; I’m
thinking that Deadwood would use quite a bit of the processing power
and memory of a WRT54G (8 megs of ram, 2 megs of flash); it may be
necessary to reduce the cache size to 512 entries to stop Deadwood
from hogging all of the memory (quick test: Deadwood uses 2.2 megs of
memory with a 512-entry cache in Windows).  It’s a good thing
Deadwood’s LRU cache design helps Deadwood run well when there are
more entries being processed than what will fit in the cache.

> I didn't ran into any trouble yet, using Deadwood since a few weeks
> (2.9.03) on my TP-Link TL-WR1043ND. One time I got a segfault, but after
> recompiling (and changing nothing) everything worked. It is possible
> that I forgot to shutdown DNSMasq which is the default resolver on
> OpenWRT before running Deadwood.

Hmmm...maybe.  I’ll blame it on cosmic rays unless we find a way to
consistently reproduce it.

> Yes, there is a strip tool, after striping the file sizes 100768 bytes.
> I used -s for striping

That’s bigger than I thought it would be.  It’s amazing how compact
the x86 instruction set is; my guess was that the overhead for RISC is
making a binary 50% bigger but it’s closer to 55% bigger.  I wonder
how large the AMD thumb ISA binary would be?  (OK, time to install an
ARM cross-compiler to find out...)

> I mainly posted here to
> reach people who are interested in getting Deadwood running off x86.

I’m very interested in that target also.  Deadwood is about as small
as a full-featured recursive DNS server can get, and I think it makes
as much sense to put it in an embedded router as on a desktop PC.