Gabriel Girard

• Head of Department at Université de Sherbrooke

Most of today’s malware are able to detect traditional debuggers and change their behavior whenever somebody tries to analyze them. The analysis of such malware becomes then a much more complex task. In this paper, we present the functionalities provided by the Kolumbo kernel module that can help simplify the analysis of malware. Four functionaliti...

Virtualization of x86 servers has been a hot topic in the last decade, culminating in changes in the architecture's design and the development of new technologies based in different approaches to provide server virtualization. In this paper, we present a comparative study of six vir- tualization technologies released under the GPL license. Our anal...

In the last decade, personal computers became more powerful and less expensive, and the development of Internet increased the connectivity of these machines. This situation opened many opportunities in the distributed computing world. Some projects such as SETI@home were launched to perform scientific computations on temporarily unused workstations...

Numerous shared memory consistency models have appeared for the purpose of obtaining better shared memory parallel computers, ones which suffer less from long memory latency. This paper uses the primitive notion of program-order and value-order to define global view. Using this as a seed, various consistency models evolve and form hierarchies of mo...

paradigm in parallel and distributed environments. However, DSM often suffers from performance problems as consistency requirements often incur long access latencies that cannot be overlapped with other operations in a process. Sequential consistency is the most general consistency requirement for DSM systems. This thesis explores two different ave...

Cause-and-eect precedence can be established between the reading of a value written by another process. Together with the local program order, the local view of a process is dened. The local views of all processes can be composed together to form the global view of a DSM. We propose a hierarchical set of augmentation rules to be applied to the glob...

Sequential consistency is a well known consistency requirement for distributed shared memory. However, most of the algorithms that implement sequential consistency involve some expensive blocking. We propose algorithms that reduce blocking. First, we propose a synchronous algorithm using a 3-phase protocol and, when it is possible, a more efficient...