Today I ran into an interesting server problem. We recently had a huge traffic spike and the servers didn't respond the way we thought they would. We thought part of the issue could be a cold Amazon ELB, but that didn't explain the load spike on the servers behind the ELB. We also looked around a bit and while the resources on the machine were elevated, none of them were at critical levels. Memory usage remained a fairly flat 40% and CPU was under 25%.