A lot of impressive tricks here to get a memcached fast path into the kernel using ebpf. They focused only on short keys and values, only on UDP, used a simple

A lot of impressive tricks here to get a memcached fast path into the kernel using ebpf. They focused only on short keys and values, only on UDP, used a simple hash table with no collision algorithm, and still had to split the code into 7 ebpf programs. Quite an achievement though, I didn't think it was possible. Also it seems udp memcached is not popular and hasn't been optimized well - it uses a single socket and spends a lot of time fighting for the kernel lock on that socket. Both the authors and Facebook patched memcached to get around that bottleneck. It's surprising that hasn't yet found its way upstream.