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This content will become publicly available on September 7, 2023

Title: LEGOStore: A Linearizable Geo-Distributed Store Combining Replication and Erasure Coding
We design and implement LEGOStore, an erasure coding (EC) based linearizable data store over geo-distributed public cloud data centers (DCs). For such a data store, the confluence of the following factors opens up opportunities for EC to be latency-competitive with replication: (a) the necessity of communicating with remote DCs to tolerate entire DC failures and implement linearizability; and (b) the emergence of DCs near most large population centers. LEGOStore employs an optimization framework that, for a given object, carefully chooses among replication and EC, as well as among various DC placements to minimize overall costs. To handle workload dynamism, LEGOStore employs a novel agile reconfiguration protocol. Our evaluation using a LEGOStore prototype spanning 9 Google Cloud Platform DCs demonstrates the efficacy of our ideas. We observe cost savings ranging from moderate (5-20%) to significant (60%) over baselines representing the state of the art while meeting tail latency SLOs. Our reconfiguration protocol is able to transition key placements in 3 to 4 inter-DC RTTs (< 1s in our experiments), allowing for agile adaptation to dynamic conditions.
Authors:
; ; ; ; ;
Award ID(s):
2122155
Publication Date:
NSF-PAR ID:
10356219
Journal Name:
Proceedings of the VLDB Endowment
Volume:
15
Issue:
10
ISSN:
2150-8097
Sponsoring Org:
National Science Foundation
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