Layer-4 load balancers are a popular solution to high tail latencies but perform poorly under unpredictable skewed workloads because they statically assign connections to servers. We present Capybara, a new load balancer architecture that enables dynamic rebalancing of established connections. Capybara divides load balancing responsibility into a fast L4 load balancer, a host-switch co-designed connection migration protocol, and a transport interface for application-level connection state migration. Capybara leverages two trends\u2013 programmable switches and kernel-bypass\u2013 to efficiently implement connection migration without disruption, while maintaining transparency to clients. Under realistic workloads, Capybara achieves up to 149\u00d7 lower tail latency and more than 2\u00d7 higher throughput for scale-out services compared to state-of-the-art load balancing approaches.<\/p>\n","protected":false},"excerpt":{"rendered":"
Layer-4 load balancers are a popular solution to high tail latencies but perform poorly under unpredictable skewed workloads because they statically assign connections to servers. We present Capybara, a new load balancer architecture that enables dynamic rebalancing of established connections. Capybara divides load balancing responsibility into a fast L4 load balancer, a host-switch co-designed connection […]<\/p>\n","protected":false},"featured_media":0,"template":"","meta":{"msr-url-field":"","msr-podcast-episode":"","msrModifiedDate":"","msrModifiedDateEnabled":false,"ep_exclude_from_search":false,"_classifai_error":"","msr-author-ordering":[{"type":"text","value":"Inho Choi","user_id":0},{"type":"text","value":"Nimish Wadekar","user_id":0},{"type":"text","value":"Guangda Sun","user_id":0},{"type":"text","value":"Raj Joshi","user_id":0},{"type":"text","value":"Joshua Fried","user_id":0},{"type":"text","value":"Omar S. 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