Load testing surprises...

We've been doing a considerable amount of load testing on the new server code recently and we've had some shocking results. The main one was a concurrency with our caching classes. We had implemented a removal queue in which objects would rise and fall based on usage. Turned out that there were some serious locking problems going on here. One of our developers reimplemented it using Doug Lea's packages util.concurrent Release 1.3.4. and the LRUMap and we've gained a considerable amount of performance.

Moral of the story, check this stuff earlier.