priyen asked me to post more info.
These are the pages to be edited. They'll look slightly different because I'm using Toastman's Tomato rather than TomatoUSB or stock Tomato.
More info on the options I chose here:
»
www.thekelleys.org.uk/dn ··· man.htmllog-async is a performance option. It needs to be somewhere between 5-25 (apparently) or large numbers of DNS requests can stall while it waits to log them.
no-negcache prevents your router from remembering that there's no domain. It checks every single time. Every once and a while overclock.net would timeout for me - some weird DNS/website glitch. After it happened I'd have to reboot my router to clear the DNS table. (until I discovered this tweak)
It happened with both Telus and Teksavvy, so it's some weird issue with where their servers were located and how they were setup. Any which way, now they're with a different host, so it's not strictly necessary.
dhcp-authoritative says that this router is the only DHCP router on the network, and must be obeyed. It apparently speeds up DHCP negotiation slightly.
Reduce packet size shrinks DNS packets to prevent ornery routers between you and the DNS servers from dropping them. Near as I can tell that one should be enabled for everyone, so I'm not sure why it's optional/visible. Unticking it caused DNS timeouts for me. (Long 20-30 second delays before webpages started to load)