Live in the Express Lane

We introduce Express-Lane (X-Lane), a novel system for mitigating interference in data center infrastructure to improve the liveness of coordination services. X-Lane follows a novel design from the ground up to achieve interactions with ultra-low latency in the single-digit microsecond range and jitter in the nanosecond range, while the remaining interaction is treated as usual. To show X-Lane's applicability and genericity we implemented and evaluated two services atop it on commodity hardware in a production environment of SAP SE: a failure detector (X-FD) with detection time under 10 μs and a Raft implementation (X-Raft) with latencies under 20 μs. We further show the smooth integrability of X-Lane services by replacing the replication protocol of Redis with X-Raft, making it strongly consistent while improving latency 18x and write throughput 1.5x.