Paxos family of protocols are employed by many cloud computing services and distributed databases due to their excellent fault-tolerance properties. Unfortunately, current Paxos deployments do not scale for more than a dozen nodes due to the communication bottleneck at the leader. PigPaxos addresses this problem by decoupling the communication from the decision-making at the leader. To this end, PigPaxos revises the communication flow in Paxos to replace direct communication between the leader and followers with a relay/aggregate based message flow. Although aggregation-based approaches have been employed in the context of weak-consistency replication protocols, PigPaxos shows how they can be effectively integrated into the strong consistency distributed consensus protocols. We implement and evaluate PigPaxos, in comparison to Paxos and EPaxos protocols under various workloads over clusters of size 5 to 25 nodes. We show that PigPaxos can provide more than 3 folds improved throughput over Paxos and EPaxos with little latency deterioration. Our experiments also show that the aggregation has negligible overhead for the latency of PigPaxos as compared to the latency of Paxos. We conjecture that PigPaxos would be useful for implementing geo-replicated distributed databases with tens of replicas distributed over many regions around the globe.

中文翻译：

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PigPaxos：吞噬分布式共识中的通信瓶颈

由于其出色的容错特性，Paxos 协议家族被许多云计算服务和分布式数据库采用。不幸的是，由于领导者的通信瓶颈，当前的 Paxos 部署不能扩展到十几个节点。PigPaxos 通过将沟通与领导者的决策分离来解决这个问题。为此，PigPaxos 修改了 Paxos 中的通信流，用基于中继/聚合的消息流代替领导者和追随者之间的直接通信。尽管在弱一致性复制协议的上下文中采用了基于聚合的方法，但 PigPaxos 展示了如何将它们有效地集成到强一致性分布式共识协议中。我们实施和评估 PigPaxos，与在大小为 5 到 25 个节点的集群上的各种工作负载下的 Paxos 和 EPaxos 协议相比。我们表明，与 Paxos 和 EPaxos 相比，PigPaxos 可以提供 3 倍以上的吞吐量提高，而延迟恶化很小。我们的实验还表明，与 Paxos 的延迟相比，聚合对于 PigPaxos 的延迟的开销可以忽略不计。我们推测 PigPaxos 将有助于实现具有分布在全球许多地区的数十个副本的地理复制分布式数据库。我们的实验还表明，与 Paxos 的延迟相比，聚合对于 PigPaxos 的延迟的开销可以忽略不计。我们推测 PigPaxos 将有助于实现具有分布在全球许多地区的数十个副本的地理复制分布式数据库。我们的实验还表明，与 Paxos 的延迟相比，聚合对于 PigPaxos 的延迟的开销可以忽略不计。我们推测 PigPaxos 将有助于实现具有分布在全球许多地区的数十个副本的地理复制分布式数据库。