I've been trying to track down randomly latency (> 1000ms) in the network stack between the socket buffer and the client for about 3 months now... All of the stack traces showed the app was stuck in futex_wait, but since it looked identical to an idle server, I'd convinced myself epoll_wait was at fault... All the sudden I'm wondering otherwise. We're not on Haswell though; it's not clear to me if the bug would affect other processors or not - can it?