Context

Datacenters are computing infrastructures that host most of the services available on the internet. As datacenters may include from thousands to millions of servers, both their energy consumption and their carbon footprint are significant. This has led many research projects to focus on optimizing these two objectives. This PhD takes place in the context of distributed datacenters where some are powered on with renewable energies while others are powered with brown energy. We will study different kinds of datacenters (private, public, …) geographically located at different places providing various energetic mix. The different datacenters are linked through a market place with collaborative or concurrent incentive to users. This PhD aims at studying new models and new behaviours (on both sides: user and cloud provider) to reach sufficiency in cloud datacenters; and evaluation of the impact of different incentives is also in the scope of the PhD.

Objective

The main objective of this PhD is to study energy efficiency and sufficiency in cloud distributed datacenters with various carbon emissions. The main tasks of this PhD are the following:

• Conduct a bibliographic survey about energy mix for datacenters and sufficiency approaches
• Propose sufficency approaches: two sides are to be studied. First, on user side: propose and study new flexibility behaviors that users could attempt. Different leverages could be considered: nodes characteristics, migration to another datacenter, new deadline. The aim is to help users to know the carbon impact of their tasks and also, to become an involved actor to reach sustainability. Second, on cloud provider side: propose new eco-* models (economic/ecologic), new low-tech behaviors. The objective of the strategy will have to be constructed and evaluated. In particular, the QoS and SLA have to be questioned. Also, the aim of the models could be for instance to maximize renewable use when available, to propose a pricing policy taking into account the energetic mix (brown energy/green energy).
• Design and implement service/data placement strategies (algorithms) that minimize the carbon footprint.
• Provide a sensibility analysis on the different factors identified in the models: for instance taking into account users behaviors, the energetic mix, low-tech cloud providers incentives…
• Evaluation will be done with simulated executions and/or real executions conducted on the Grid’5000/Slices-fr testbed.

Expected skills and profile

Required: Currently in a Master in computer science. Required: Written English. French is a plus. Strongly recommended: A taste for experimental approaches and programming. Appreciated: Background in optimization, performance evaluation and modelling.

At the end of the PhD, the student will have acquired the following skills: scientific work and experimentations, expertise in cloud and renewable energies, planning of long term projects, scientific writing.

This project involves many academic partners in France, the PhD will therefore be done in a national collaboration context. It is expected to have three annual meetings in other cities in France during which English will be used.

If willing, the student will have the opportunity to teach in English or French.

Practical details

PhD will take place at IRIT, the largest computer science research institute in Toulouse, Our team SEPIA works on resource management on various distributed systems (cloud datacenters, edge architectures, IoT. . . ) and is especially interested in ecological transition, sufficiency, by reducing energy consumption and CO2 emissions, by using renewable energy. It will be supervised by Jean-Marc Pierson and Patricia Stolf. It will be co-advised by Laurent Lefevre (Inria Avalon team, Ecole Normale Supérieure of Lyon) who works on improving energy efficiency and reducing environmental impacts of large scale distributed systems. This PhD will be funded by the CareCloud project of the PEPR Cloud collaborative project. This project involves many academic partners in France, the PhD will therefore be done in a national collaboration context. The monthly gross salary is slightly more than 2050 €.

You can send us your application (cover letter + resume / short curriculum vitæ + transcript of records for the full bachelor and current master) by email to pierson@irit.fr and patricia.stolf@irit.fr and laurent.lefevre@ens-lyon.fr