Alain Tchana

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Domain Specific Languages (DSL) are increasingly used in software engineering and other domains. The result is an increasing need of appropriate DSL's tools, especially platform for building, editors and runtime associated with DSLs. Different experiences show that existent DSL tools are generally not user friendly enough, or simply unadapted for the(More)
Fault tolerance in cloud computing platforms and applications is a crucial issue. This issue is especially difficult since cloud computing relies by nature on a complex splitting into many layers. From a technical point of view, most cloud computing platforms exploit virtualization, which implies that they are split into 3 layers: hosts, virtual machines(More)
Nowadays, virtualization is present in almost all computing infrastructures. Thanks to VM migration and server consolidation, virtualization helps reducing power consumption in distributed environments. On another side, Dynamic Voltage and Frequency Scaling (DVFS) allows servers to dynamically modify the processor frequency (according to the CPU load) in(More)
Nowadays, computer clusters are widely used in many areas (scientific computing, commercial web servers, databases, etc). Energy management in such infrastructures is becoming increasingly important as their energy consumption is continuing to raise. In this paper, we report on our experiments in using an autonomic management system to provide energy aware(More)
Cloud computing is nowadays a popular technology for hosting IT services. However, deploying and reconfiguring complex applications involving multiple software components, which are distributed on many virtual machines running on single or multi-cloud platforms, is error-prone and time-consuming for human administrators. Existing deployment frameworks are(More)
Scheduling has a significant influence on application performance. Deciding on a quantum length can be very tricky, especially when concurrent applications have various characteristics. This is actually the case in virtualized cloud computing environments where virtual machines from different users are colocated on the same physical machine. We claim that(More)
Software applications providers have always been required to perform load testing prior to launching new applications. This crucial test phase is expensive in human and hardware terms, and the solutions generally used would benefit from further development. In particular, designing an appropriate load profile to stress an application is difficult and must(More)