Providing fairer resource allocation for multi-tenant cloud-based systems

A fundamental premise in cloud computing is trying to provide a more sophisticated computing resource sharing capability. In order to provide better allocation, the Dominant Resource Fairness (DRF) approach has been developed to address the "fair resource allocation problem" at the application layer for multi-tenant cloud applications. Nevertheless conventional DRF only considers the interplay of CPU and memory, which may result in over allocation of resources to one tenant's application to the detriment of others. In this paper, we propose an improved DRF algorithm with 3-dimensional demand vector to support disk resources as the third dominant shared resource, enhancing fairer resource sharing. Our technique is integrated with LINUX 'group' controls resource utilisation and realises data isolation to avoid undesirable interactions between co-located tasks. Our method ensures all tenants receive system resources fairly, which improves overall utilisation and throughput as well as reducing traffic in an over-crowded system. We evaluate the performance of different types of workload using different algorithms and compare ours to the default algorithm. Results show an increase of 15% resource utilisation and a reduction of 59% completion time on average, indicating that our DRF algorithm provides a better, smoother, fairer high-performance resource allocation scheme for both continuous workloads and batch jobs.

The impossible anamesis. Memory versus history in Hubert Aquin’s « Blackout »

Soon after joining the Canadian Confederation in 1867, the province of Quebec adopted the phrase « Je me souviens » ("As I recall") as its "national" motto, although many Québécois do not remember today what they were supposed to memorize, as collective subject, when their government voted this motion. My thesis is that contrary to other countries which have a strong sense of history based on a secular tradition, this process was more complicated in Quebec — as if a collective memory loss lied at the heart of it's history. Through a rereading of Hubert Aquin's cult novel, Trou de mémoire (in its English translation Blackout), first published in 1968, I try to illustrate this paradox and to emphasize the heuristic functions of memory blanks, gaps and lapses in certain postmodern narratives, after the historical breakdown of "the great narratives" (Lyotard). In this perspective, the example of Quebec, through the voice of one of its more gifted yet controversial novelist, can be seen as emblematic of what happens when the mnemonic impossibility of rewriting history opens up new possibilities for writing fiction.

Integration of a graph-based model indexer in commercial modelling tools

Softeam has over 20 years of experience providing UML-based modelling solutions, such as its Modelio modelling tool, and its Constellation enterprise model management and collaboration environment. Due to the increasing number and size of the models used by Softeam’s clients, Softeam joined the MONDO FP7 EU research project, which worked on solutions for these scalability challenges and produced the Hawk model indexer among other results. This paper presents the technical details and several case studies on the integration of Hawk into Softeam’s toolset. The first case study measured the performance of Hawk’s Modelio support using varying amounts of memory for the Neo4j backend. In another case study, Hawk was integrated into Constellation to provide scalable global querying of model repositories. Finally, the combination of Hawk and the Epsilon Generation Language was compared against Modelio for document generation: for the largest model, Hawk was two orders of magnitude faster.

The impossible anamesis. Memory versus history in Hubert Aquin’s « Blackout »

Soon after joining the Canadian Confederation in 1867, the province of Quebec adopted the phrase « Je me souviens » ("As I recall") as its "national" motto, although many Québécois do not remember today what they were supposed to memorize, as collective subject, when their government voted this motion. My thesis is that contrary to other countries which have a strong sense of history based on a secular tradition, this process was more complicated in Quebec — as if a collective memory loss lied at the heart of it's history. Through a rereading of Hubert Aquin's cult novel, Trou de mémoire (in its English translation Blackout), first published in 1968, I try to illustrate this paradox and to emphasize the heuristic functions of memory blanks, gaps and lapses in certain postmodern narratives, after the historical breakdown of "the great narratives" (Lyotard). In this perspective, the example of Quebec, through the voice of one of its more gifted yet controversial novelist, can be seen as emblematic of what happens when the mnemonic impossibility of rewriting history opens up new possibilities for writing fiction.

Health profile of centenarians in Portugal: a census-based approach

Background: The number of centenarians is rapidly increasing in Europe. In Portugal, it has almost tripled over the last 10 years and constitutes one of the fastest-growing segments of the population. This paper aims to describe the health and sociodemographic characteristics of Portuguese centenarians as given in the 2011 census and to identify sex differences. Methods: All persons living in Portugal mainland and Madeira and Azores islands aged 100 years old at the time of the 2011 census (N = 1,526) were considered. Measures include sociodemographic characteristics and perceived difficulties in six functional domains of basic actions (seeing, hearing, walking, cognition, self-care, and communication) as assessed by the Portuguese census official questionnaires. Results: Most centenarians are women (82.1 %), widowed (82 %), never attended school (51 %), and live in private households (71 %). The majority show major constraints in seeing (67.4 %), hearing (72.3 %), and particularly in their mobility (83.7 % cannot/have great difficulties in walking/climbing stairs and 80.7 % in bathing/dressing). In general, a better outcome was found for reported memory/concentration and understanding, with 39.1 % and 42.5 % presenting no or mild difficulty, respectively. Top-level functioning (no/mild difficulties in all dimensions concurrently) was observed in a minority of cases (5.96 %). Women outnumber men by a ratio of 4.6, and statistically significant differences were found between men and women for all health-related variables, with women presenting a higher percentage of difficulties. Conclusion: Portuguese centenarians experience great difficulties in sensory domains and basic daily living activities, and to a lesser extent in cognition and communication. The obtained profile, though self-reported, is important in considering the potential of social and family participation of this population regardless of their functional and sensory limitations. Based on the observed differences between men and women, gender-specific and gender-sensitive interventions are recommended in order to acknowledge women’s worse overall condition.

Trace memory: after decay

In this exhibition, interdisciplinary artist Tonya A. Meyrick presents a body of new work that explores the relationship between memory and place.Tonya A. Meyrick explores the recollection and perception of memory and considers how our memories are not stable; rather, they are fickle and tied to the places which we inhabit, past events and the ebb and flow of our daily patterns. The act of remembering, putting our memories back together is the thread that runs through this exhibition of large format digital still and moving artworks coupled with an experience of augmented reality