Leonardo Marques Epifânio


Cathode: A Consistency-Aware Data Placement Algorithm for the Edge


Tese submetida para provas de mestrado em Engenharia Informática e de Computadores Instituto Superior Técnico, Universidade de Lisboa.

Abstract

Placing data replicas in edge nodes is a key strategy to offer low latency to clients and to improve network utilization. In the case of immutable objects, data placement is only constrained by the limited capacity of edge nodes. However, for mutable objects, one also needs to consider the cost of keeping replicas consistent, which then varies with the data consistency model: a replica placement algorithm that performs well for weakly consistent replicas may perform poorly when strong consistency is required. In this thesis, we present Cathode, a replica placement algorithm that is tailored for the requirements of the edge environment, all the while being consistency-aware, making placement decisions based on client demand, storage costs, and the costs of keeping replicas consistent. In the underlying system, different objects may use different consistency models and Cathode makes placement decisions accordingly. Because optimal replica placement is known to be an NP-hard problem, Cathode resorts to an heuristic that is decentralized and scalable, providing fast convergence, but also achieving high quality deployments. The extensive performance evaluation reported in this thesis shows that it outperforms previous state-of-the-art replica placement algorithms.

Publicações

Cathode: A Consistency-Aware Data Placement Algorithm for the Edge
Leonardo Marques Epifânio
MSc Thesis. Instituto Superior Técnico, Universidade de Lisboa.
January 2021.
Available BibTeX, MSC Thesis, and extended abstract, and mid-term report.
Cathode: A Consistency-Aware Data Placement Algorithm for the Edge.
L. Epifânio, C. Correia and L. Rodrigues.
Proceedings of the 20th IEEE International Symposium on Network Computing and Applications (NCA 2021), Online, November, 2021.

Luís Rodrigues