Reducing Tail Latency via Safe and Simple Duplication

Hafiz Mohsin Bashir; Abdullah Bin Faisal; Muhammad Asim Jamshed; Peter Vondras; Ali Musa Iftikhar; Ihsan Ayyub Qazi; Fahad R. Dogar

arXiv · 1905.13352

Reducing Tail Latency via Safe and Simple Duplication

Hafiz Mohsin Bashir·Abdullah Bin Faisal·Muhammad Asim Jamshed·Peter Vondras·Ali Musa Iftikhar·Ihsan Ayyub Qazi·Fahad R. Dogar

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Abstract

Duplication can be a powerful strategy for overcoming stragglers in cloud services, but is often used conservatively because of the risk of overloading the system. We present duplicate-aware scheduling or DAS, which makes duplication safe and easy to use, by leveraging the two well-known primitives of prioritization and purging. To support DAS across diverse layers of a cloud system (e.g., network, storage, etc), we propose the D-Stage abstraction, which decouples the duplication policy from the mechanism, and facilitates working with legacy layers of a system. Using this abstraction, we evaluate the benefits of DAS for two data parallel applications (HDFS, an in-memory workload generator) and a network function (snort-based IDS cluster). Our experiments on the public cloud and Emulab show that DAS is safe to use, and the tail latency improvement holds across a wide range of workloads

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Hafiz Mohsin Bashir, Abdullah Bin Faisal, Muhammad Asim Jamshed, Peter Vondras, Ali Musa Iftikhar, Ihsan Ayyub Qazi, Fahad R. Dogar. 2019-05-30. Reducing Tail Latency via Safe and Simple Duplication. https://arxiv.org/abs/1905.13352

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