Energy Consumption Management and Optimization in a

Le descriptif de l’offre ci-dessous est en Anglais_

**Type de contrat **:CDD

**Niveau de diplôme exigé **:Bac + 5 ou équivalent

**Fonction **:Ingénieur scientifique contractuel

**Niveau d'expérience souhaité **:De 3 à 5 ans

**A propos du centre ou de la direction fonctionnelle**:
The Inria center at the University of Bordeaux is one of the nine Inria centers in France and has about twenty research teams.. The Inria centre is a major and recognized player in the field of digital sciences. It is at the heart of a rich R&D and innovation ecosystem: highly innovative SMEs, large industrial groups, competitiveness clusters, research and higher education players, laboratories of excellence, technological research institute...

**Contexte et atouts du poste**:
**Context**

Electricity is a cornerstone of life. Neurons generate electric currents across their cell membrane to transport signals, skeletal muscle cells do so to trigger their contraction, and cardiac muscle cells do both, synchronizing electrically to coordinate contraction across the heart muscle. Malfunctions in cellular electrical systems can have disastrous effects on the organism. Electrical disorders are responsible for half of all cardiac diseases, the most frequent cause of death in the world.

Cellular electric activity is generated by the interaction of many different proteins that are embedded in the cell membrane. Numerical models are vital to understand these complex systems. Yet, realistic simulations of cardiac electrophysiology in structurally abnormal tissue require discretization of the individual cells and their interconnections. This means at least a factor 10^5 increase in model size compared to the usual homogenized models, as well as a different model formulation. This does not only require exascale or larger supercomputers but also a joint effort of biomedical engineers, mathematicians, and computer scientists to build a platform that runs effectively on these machines.

**Objectives**

Powerful time

Energy efficiency will also be handled by the runtime system at the node level. On heterogeneous architectures, choosing the right computing unit to perform each computation can reduce energy consumption. Depending on the task’s characteristics, allowing a small performance degradation can lead to large energy savings. Also data movement has an important effect on both performance and energy consumption. This cost should be considered when placement of computations implies data movement. Powercapping may also help to reduce energy usage. In some cases using more nodes while enforcing a powercap provides better performance than using fewer nodes at their maximum limit. The power budget for each task must therefore be determined. In order to dynamically set the powercap, we will benefit from the performance models already provided by the StarPU task-based runtime system developed by Inria team STORM, and augment them with powercap impact, after studying the impact of power capping on the performance models.

**Mission confiée**:
Load imbalance as incurred by imperfect mesh partitioning, algebraic adaptivity, direct solver fill-in, or solution-dependent solver iteration count can be exploited to reduce power consumption and energy use. **The first part of the mission** will be to derive rough predictions of the computational work to be done on each device up to the next synchronization barrier, and then to implement throttling techniques such as enforcing a lower frequency scaling (when available), a lower parallelism degree, or the selection of kernel variants with lower energy consumption profiles.

**Principales activités**:
Main activities (5 maximum):

- Ensure the continuous integration and the quality control of software developments.
- Conduct validation and performance evaluation experiments.
- Participate to software documentation, timely deliverable preparation and reporting, and dissemination & transfer efforts within the project and the community

**Compétences**:
Fluent skills are required in the following activities:

- C / C++ programming
- Software development in the Unix environment
- Parallel and distributed programming
- Remote development and operating using ssh
- Development using a version control system such as Git
- Continuous integration using a system such as GitLab-CI

Good technical and scientific skills in both written and oral English are necessary to successfully conduct the mission, interact with the project partners and prepare reporting documents.

**Avantages**:

- Subsidized meals
- Partial reimbursement of public transport costs
- Leave: 7 weeks of annual leave + 10 extra days off due to RTT (statutory reduction in working hours) + possibility of exceptional leave (sick children, moving home, etc.)
- Possibility of teleworking and flexible organization of working hours
- Professional equipment available (videoconferencing, loan of computer equipment, etc.)
- Social, cultural and