Barnacle：面向基于DAG的共识的自适应多领导者调度

中文摘要 AI 辅助

在基于DAG的共识机制中，所有验证者会并行提议区块，指定的领导者区块推动交易提交。每轮设置多个领导者槽位可降低排队延迟，但实际生产部署中却仅使用单个领导者，原因存在队头阻塞问题：一个缓慢的领导者会使流水线至少停滞一个领导者超时时间，若其槽位需等待 fallback 间接决策规则，还会导致多轮停滞，且该风险随领导者数量增加而上升。本文提出 Barnacle，这一可在运行时自适应调整领导者数量的附加组件。每间隔一段时间，它会在已达成提交的DAG上，测量通过直接规则被判定为提交的槽位占比，并采用加性增加、乘性减少的策略调整领导者数量。该测量无需额外消息和密码学操作，且具有确定性。Barnacle 对DAG协议具有通用性；我们在涵盖拜占庭故障模型（3f + 1、5f + 1）、仅崩溃故障模型（2c + 1）及混合故障模型（5f + 3c + 1）的四种协议上进行了实例化，且已证明其安全性和活性。实验结果显示，Barnacle 在所有场景下均能达到最佳静态领导者数量的表现：在健康网络中，其延迟比单个领导者低6%-13%；在网络退化情况下，其表现与单个领导者相当，同时比静态高领导者数量的情况低35%-56%。目前我们正与 Sui 团队合作，将 Barnacle 集成到 Sui 区块链中。

英文摘要

In DAG-based consensus, all validators propose blocks concurrently, and designated leader blocks drive transaction commit. Having multiple leader slots per round cuts queuing latency, yet production deployments run a single leader because of head-of-line blocking: a slow leader stalls the pipeline for at least one leader timeout, and for several waves when its slot must wait for the fallback indirect decision rule. This risk grows with the leader count. We introduce Barnacle, an add-on that adapts the leader count at run time. Every interval, it measures on the agreed committed DAG the fraction of slots decided as commit by the direct rule, and drives the leader count with additive increase, multiplicative decrease. The measurement requires no extra messages and no cryptography, and is deterministic. Barnacle is generic over DAG protocols; we instantiate it on four protocols spanning the Byzantine (3f + 1, 5f + 1), crash-only (2c + 1), and mixed (5f + 3c + 1) fault models, with proven safety and liveness. Results show Barnacle matches the best static leader count in every regime: in a healthy network its latency is 6-13% lower than a single leader's, and under degradation it matches a single leader while remaining 35-56% below a static high count. We are currently collaborating with the Sui team to integrate Barnacle into the Sui blockchain.

发表机构

• Mysten Labs
• Columbia University（哥伦比亚大学）
• University College London (UCL)（伦敦大学学院）
• Digital Asset

机构由 AI 辅助整理，请以论文原文为准。