One Paper Has Been Accepted to Euro-Par 2021 -
Geo-Distribute Cloud Applications at the Edge
Ronan-Alexandre Cherrueau, Marie Delavergne, Adrien Lebre
With the arrival of the edge computing a new challenge arise for cloud applications: How to benefit from geo-distribution (locality) while dealing with inherent constraints of wide-area network links? The admitted approach consists in modifying cloud applications by entangling geo-distribution aspects in the business logic using distributed data stores. However, this makes the code intricate and contradicts the software engineering principle of externalizing concerns. We propose a different approach that relies on the modularity property of microservices applications: (i) one instance of an application is deployed at each edge location, making the system more robust to network partitions (local requests can still be satisfied), and (ii) collaboration between instances can be programmed outside of the application in a generic manner thanks to a service mesh. We validate the relevance of our proposal on a real use-case: geo-distributing OpenStack, a modular application composed of 13 million of lines of code and more than 150 services.