A Cost-Sensitive Adaptation Engine for Server Consolidation of Multitier Applications

Abstract. Virtualization-based server consolidation requires runtime resource reconfiguration to ensure adequate application isolation and performance, especially for multitier services that have dynamic, rapidly changing workloads and responsiveness requirements. While virtualization makes reconfiguration easy, indiscriminate use of adaptations such as VM replication, VM migration, and capacity controls has performance implications. This paper demonstrates that ignoring these costs can have significant impacts on the ability to satisfy response-time-based SLAs, and proposes a solution in the form of a cost-sensitive adaptation engine that weighs the potential benefits of runtime reconfiguration decisions against their costs. Extensive experimental results based on live workload traces show that the technique is able to maximize SLA fulfillment under typical time-of-day workload variations as well as flash crowds, and that it exhibits significantly improved transient behavior compared to approaches that do not account for adaptation costs.

Community-based broadband organizations and video communications for remote and rural First Nations in Canada

Our research is building understanding about how two community-based First Nations organizations in Canada are using video communications on broadband networks to support economic and social development in remote and rural First Nations. This study situates these two organizations within a broader social movement working toward self-determination for First Nations in Canada, exploring their use of video communications in this context. Video communications using broadband networks includes videoconferences (live and archived) and online videos. The research methodology for this study includes a content analysis of hundreds of archived videoconferences and videos on the servers of the two organizations as well as interviews with key informants using these technologies to develop remote and rural First Nations communities.Cette recherche nous permettra de mieux comprendre comment deux organisations communautaires des Premi\ue8res nations du Canada se servent des communications vid\ue9o sur r\ue9seaux \ue0 tr\ue8s large bande pour favoriser le d\ue9veloppement \ue9conomique et social de communaut\ue9s \ue9loign\ue9es et rurales des Premi\ue8res nations. La pr\ue9sente \ue9tude situe ces deux organisations dans le contexte plus vaste d'un mouvement social \u153uvrant en vue de l'autod\ue9termination des Premi\ue8res nations au Canada, et explore leur utilisation des communications vid\ue9o dans ce cadre. Les communications vid\ue9o faisant appel \ue0 des r\ue9seaux \ue0 tr\ue8s large bande comprennent des vid\ue9oconf\ue9rences (en direct et archiv\ue9es) et des vid\ue9os en ligne. Le plan m\ue9thodologique retenu pour cette recherche comprend une analyse de contenu appliqu\ue9e \ue0 des centaines de vid\ue9oconf\ue9rences archiv\ue9es et \ue0 des vid\ue9os sur les serveurs des deux organisations, ainsi que des interviews avec des informants cl\ue9s qui utilisent ces technologies pour promouvoir le d\ue9veloppement des communaut\ue9s des Premi\ue8res nations \ue9loign\ue9es et rurales.NRC publication: Ye