conference paper published yes Pasindu Tennage author Cristina Basescu author Eleftherios Kokoris Kogias author f5983044-d7ef-11ea-ac6d-fd1430a26d300000-0002-8827-3382 Ewa Syta author Philipp Jovanovic author Vero Estrada-Galinanes author Bryan Ford author ElKo department SOSP: Symposium on Operating Systems Principles Leader-based consensus algorithms are fast and efficient under normal conditions, but lack robustness to adverse conditions due to their reliance on timeouts for liveness. We present QuePaxa, the first protocol offering state-of-the-art normal-case efficiency without depending on timeouts. QuePaxa uses a novel randomized asynchronous consensus core to tolerate adverse conditions such as denial-of-service (DoS) attacks, while a one-round-trip fast path preserves the normal-case efficiency of Multi-Paxos or Raft. By allowing simultaneous proposers without destructive interference, and using short hedging delays instead of conservative timeouts to limit redundant effort, QuePaxa permits rapid recovery after leader failure without risking costly view changes due to false timeouts. By treating leader choice and hedging delay as a multi-armed-bandit optimization, QuePaxa achieves responsiveness to prevalent conditions, and can choose the best leader even if the current one has not failed. Experiments with a prototype confirm that QuePaxa achieves normal-case LAN and WAN performance of 584k and 250k cmd/sec in throughput, respectively, comparable to Multi-Paxos. Under conditions such as DoS attacks, misconfigurations, or slow leaders that severely impact existing protocols, we find that QuePaxa remains live with median latency under 380ms in WAN experiments. Association for Computing Machinery2023Koblenz, Germany eng 9798400702297 00113507290001810.1145/3600006.3613150 281-297 Tennage P, Basescu C, Kokoris Kogias E, Syta E, Jovanovic P, Estrada-Galinanes V, Ford B. 2023. QuePaxa: Escaping the tyranny of timeouts in consensus. Proceedings of the 29th Symposium on Operating Systems Principles. SOSP: Symposium on Operating Systems Principles, 281–297. P. Tennage, C. Basescu, E. Kokoris Kogias, E. Syta, P. Jovanovic, V. Estrada-Galinanes, B. Ford, in:, Proceedings of the 29th Symposium on Operating Systems Principles, Association for Computing Machinery, 2023, pp. 281–297. Tennage, Pasindu, Cristina Basescu, Eleftherios Kokoris Kogias, Ewa Syta, Philipp Jovanovic, Vero Estrada-Galinanes, and Bryan Ford. “QuePaxa: Escaping the Tyranny of Timeouts in Consensus.” In <i>Proceedings of the 29th Symposium on Operating Systems Principles</i>, 281–97. Association for Computing Machinery, 2023. <a href="https://doi.org/10.1145/3600006.3613150">https://doi.org/10.1145/3600006.3613150</a>. Tennage P, Basescu C, Kokoris Kogias E, et al. QuePaxa: Escaping the tyranny of timeouts in consensus. In: <i>Proceedings of the 29th Symposium on Operating Systems Principles</i>. Association for Computing Machinery; 2023:281-297. doi:<a href="https://doi.org/10.1145/3600006.3613150">10.1145/3600006.3613150</a> P. Tennage <i>et al.</i>, “QuePaxa: Escaping the tyranny of timeouts in consensus,” in <i>Proceedings of the 29th Symposium on Operating Systems Principles</i>, Koblenz, Germany, 2023, pp. 281–297. Tennage, P., Basescu, C., Kokoris Kogias, E., Syta, E., Jovanovic, P., Estrada-Galinanes, V., &#38; Ford, B. (2023). QuePaxa: Escaping the tyranny of timeouts in consensus. In <i>Proceedings of the 29th Symposium on Operating Systems Principles</i> (pp. 281–297). Koblenz, Germany: Association for Computing Machinery. <a href="https://doi.org/10.1145/3600006.3613150">https://doi.org/10.1145/3600006.3613150</a> Tennage, Pasindu, et al. “QuePaxa: Escaping the Tyranny of Timeouts in Consensus.” <i>Proceedings of the 29th Symposium on Operating Systems Principles</i>, Association for Computing Machinery, 2023, pp. 281–97, doi:<a href="https://doi.org/10.1145/3600006.3613150">10.1145/3600006.3613150</a>. 147432024-01-08T12:54:35Z2026-06-18T17:38:12Z