Jordi Guitart Fernández

A Survey on Performance Management for Internet Applications

Internet applications have become indispensable for many business and personal processes, turning the performance of these applications into a key issue. For this reason, recent research has comprehensively explored mechanisms for managing the performance of these applications, with special focus on dealing with overload situations and providing QoS guarantees to clients. This paper makes a survey on the different proposals in the literature for managing Internet applications’ performance. We present a complete taxonomy that characterizes and classifies these proposals into several categories including request scheduling, admission control, service differentiation, dynamic resource management, service degradation, control theoretic approaches, works using queuing models, observation-based approaches that use runtime measurements, and overall approaches combining several mechanisms. For each work, we provide a brief description in order to provide the reader with a global understanding of the research progress in this area.

Extended Resource Management Using Client Classification and Economic Enhancements

Commercialization of computing resources will become more and more important as the transition from Grid computing in academic environments to commercial services based on concepts such as utility or Cloud computing progresses. This results in the necessity to not only base components on technical aspects, but also to include economical aspects in their design. This paper presents a framework that links technical and economical aspects to the management of computational resources. Economic enhancements like dynamic pricing and client classification are introduced based on a technical resource management environment and positioned within this resulting in a proposed architecture for an Economically Enhanced Resource Manager (EERM). The introduced approach is evaluated considering various economic design criteria and example scenarios.

ASCETiC - Adapting Service lifeCycle towards EfficienT Clouds

Reducing energy consumption is increasingly gaining attention in the area of Cloud computing, as means to reduce costs and improve corporate sustainability image. ASCETiC is focused on providing novel methods and tools to support software developers to optimise energy efficiency and minimise the carbon footprint resulting from developing, deploying and running software in Clouds. At the same time, quality of service, experience and perception are still taken into account, so energy efficiency will complement them and boost Cloud efficiency at several dimensions. ASCETiC primary focus is to relate software design and energy use, which will depend on the deployment conditions and the correct operation of the software by means of an adaptive environment. This paper presents specific objectives for the project, as well as requirements, business goals and architecture for the resultant Open Source Cloud stack providing energy efficiency at software, platform and infrastructure Cloud layers.

Client classification policies for SLA negotiation and allocation in shared cloud datacenters

Economic models can motivate resource providers to share resources across multiple administrations in Grid computing. Our survey on existing economic models in Grid computing identified that different economic models are suitable for different scenarios. In this paper, we conduct an experiment to quantify the strengths and weaknesses of widely proposed economic models in the Grid Commodity Market, Continuous Double Auction, English Auction, Contract-Net-Protocol and Bargaining. Based on this experimental analysis, we identify regions where a particular economic model outperforms others. Then, we indicate that switching between the economic models could be used to maximize benefits in a specific scenario.In Utility Computing business model, the owners of the computing resources negotiate with their potential clients to sell computing power. The terms of the Quality of Service (QoS) to be provided as well as the economic conditions are established in a Service-Level Agreement (SLA). There are situations in which providers must differentiate the SLAs in function of the type of Client that is willing to access the resources or the agreed QoS e.g. when the hardware resources are shared between users of the company that own the resources and external users. This paper proposes to consider the information of potential users when the SLA is under negotiation to allow providers to prioritize users (e.g. internal users over external users, or preferential users over common users). Two policies for negotiation are introduced: price discrimination and client-aware overselling of resources. The validity of the policies is demonstrated through exhaustive experiments.