Context

Data centers are computing infrastructures that host most of the services available on the internet. As data centers may include thousands 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 internship takes place in the context of centralized (Cloud) and decentralized (Edge, Fog) infrastructures.

Various ideas emerge from research / R&D to reduce the impact of computing infrastructures, and these ideas must be evaluated. Doing such evaluations on real infrastructures is unfeasible, as this would induce a tremendous time and energy cost. Consequently, most evaluations are instead done in simulation, where models of applications are executed on models of computing resources. In this internship, we will focus on the SimGrid-based simulator Batsim.

Batsim has been designed with batch applications in mind. Batch applications first read input data, then issue some computations, then finally write output data and terminate. Batch applications are omnipresent in high performance computing (the context from which Batsim originated), but Cloud and Edge infrastructure mostly host service applications instead. Service applications have a long (infinite) lifecycle and adapt their shape and behavior dynamically depending on the load. As we write these lines, Batsim does not easily enable to model service applications.

Objective

The main objective of this internship is to extend Batsim capacities so that it can simulate service applications. More precisely, the objectives of this internship are the following.

• Conduct a bibliographic survey about the service application models in Cloud simulators.
• Select a service application model from the literature and implement it in Batsim.
• Instanciate the selected application model on service applications.
• Implement service placement algorithms in Batsim.
• Evaluate the behavior of service applications depending on the placement algorithm that is used. This evaluation will include several metrics such as response time and energy consumption.

Expected skills and profile

• Required: Currently in a master’s in computer science.
• Required: Fluent French or English.
• Strongly recommended: A taste for experimental approaches, C, C++ or Python programming.
• Recommended: A taste for contributing to open source projects.
• Appreciated: Background in optimization, performance evaluation and modeling.

Practical details

The internship will take place at IRIT, the largest computer science research institute in Toulouse, France. Our team SEPIA works on resource management on various distributed systems (cloud datacenters, HPC centers, edge architectures, IoT…) and is especially interested in ecological transition, notably by reducing energy consumption and CO2 emissions, by using renewable energy.

It will be supervised by Millian Poquet and Patricia Stolf in a convivial atmosphere :).

This internship will be funded by the CareCloud project of the PEPR Cloud collaborative project. The monthly gross salary will be of 591 €.

An open PhD position on the simulation of service applications will also be funded by the CareCloud project of the PEPR Cloud collaborative project. The CareCloud project involve many academic partners in France, the PhD will therefore be done in a national collaboration context.

You can send us your application (cover letter + resume + transcript of records for the full bachelor and current master) by email to millian.poquet@irit.fr and patricia.stolf@irit.fr.