擴展伯克利封包過濾器 (eBPF) 提供了一種直接在 Linux 核心中動態載入和 執行微程式的變革性方法，從而避免了核心重新編譯的需要。本文探討了 eBPF 在優化基於 gossip 的叢集環境中的資源使用方面的創新應用。我們的 主要重點是部署用於核心資料包克隆的 TC eBPF 掛鉤，旨在提高用戶空間廣 播的效率。這種方法在像 Gossip 這樣嚴重依賴用戶空間廣播機制的共識演 算法中尤其關鍵。我們探索了這種方法的實施，強調了它顯著提高廣播速度 的能力。我們的研究結果表明，在基於 Gossip 的系統中，CPU 使用率顯著 提高，降低了 29%，傳輸頻寬提高了 2.67 倍。這項研究展示了 eBPF 在減少 網路協定堆疊和系統呼叫開銷方面的潛力，從而顯著優化了分散式共識演算 法中典型的用戶空間廣播行為。

The Extended Berkeley Packet Filter (eBPF) presents a transformative approach to dynamic micro-program loading and execution directly within the Linux kernel, cir- cumventing the need for kernel recompilation. This paper explores the innovative application of eBPF in optimizing resource usage within gossip-based cluster en- vironments. Our primary focus is the deployment of TC eBPF hooks for in-kernel packet cloning, aiming to enhance the efficiency of user-space broadcasts. This ap- proach is particularly pivotal in consensus algorithms like Gossip, which heavily rely on user-space broadcast mechanisms. We explore the implementation of this method, highlighting its ability to boost broadcast speeds significantly. Our find- ings reveal a marked improvement in CPU utilization, which decreased by 29%, and in Transmit Bandwidth, which increased by a factor of 2.67, in Gossip-based systems. This research demonstrates the potential of eBPF in reducing the overhead of network protocol stacks and system calls, which significantly optimizes the typ- ical user-space broadcast behavior found in distributed consensus algorithms.

1 Introduction 1 1.1 GossipProtocol............................ 1 1.2 ChallengesinGossipProtocols.................... 2 1.3 AdvancedImplementationTechniques................ 2 1.4 OptimizingGossipProtocolswitheBPF . . . . . . . . . . . . . . . 2
2 Background 4
2.1 Gossipprotocol............................ 4
2.2 eBPF ................................. 6
2.2.1 BPFHooks&Map ..................... 6
2.2.2 bpf_syscallandlifecycle................... 7
2.3 OptimizingnetworkdatapathusingeBPF . . . . . . . . . . . . . . 11 2.3.1 TCHook&XDPHook ................... 11
2.4 KernelBypassusingAF_XDP .................... 12
3 Design 16
3.1 eGossipOverview........................... 16
3.2 eGossipDesign ............................ 18
3.2.1 In-kernelBroadcaster..................... 18 3.2.2 Communicatingwiththekernelspace . . . . . . . . . . . . 22 3.2.3 Receiverwithkernelbypass ................. 23
4 Implementation 27
5 Evaluation 29 5.1 EnvironmentandMethodology.................... 29 5.2 Profiling................................ 30 5.3 CPUUtilization............................ 31 5.4 FixedSizeThroughputandCPUAnalysis . . . . . . . . . . . . . . 33
6 Conclusion References 37
References. 39

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