Wise Bread has been very popular on Digg the last few weeks. Every time we get Dugg, the server crawls. We've been making incremental tweaks, but today, we found a tweak that relieved all the pressure at once:

Throttle the statistics module!

It's been said before, but we didn't do it in order to preserve the list of popular today/all-time articles in the sidebar. Everything else we throttled. For previous Diggings, that level of throttling along with making the popular article a static file was just enough to make the site load very slowly. (That's better than when we were getting WSOD or 503 unavailables.)

Today when the number of anonymous users online stayed high (around 1800) for a couple of hours (and the site was unresponsive), we knew more stuff had to go. As soon as we throttled statistics, search and comments, the load on the server dropped to zero. We ended up unthrottling comments and the load was still acceptable, so we'll keep that on. But definitely no more statistics during high load conditions.

Bottom line: If you want your content (at least the article) to be read during a Digging, throttle aggressively. Throw out everything except the article itself if you have to!