CumuloNimbo: Una plataforma como servicio con procesamiento transaccional altamente escalable.

El modelo de computaci¿on en la nube (cloud computing) ha ganado mucha popularidad en los últimos años, prueba de ello es la cantidad de productos que distintas empresas han lanzado para ofrecer software, capacidad de procesamiento y servicios en la nube. Para una empresa el mover sus aplicaciones a la nube, con el fin de garantizar disponibilidad y escalabilidad de las mismas y un ahorro de costes, no es una tarea fácil. El principal problema es que las aplicaciones tienen que ser rediseñadas porque las plataformas de computaci¿on en la nube presentan restricciones que no tienen los entornos tradicionales. En este artículo presentamos CumuloNimbo, una plataforma para computación en la nube que permite la ejecución y migración de manera transparente de aplicaciones multi-capa en la nube. Una de las principales características de CumuloNimbo es la gestión de transacciones altamente escalable y coherente. El artículo describe la arquitectura del sistema, así como una evaluaci¿on de la escalabilidad del mismo

Transaction management across data stores

Companies have evolved from a world where they only had SQL databases to a world where they use different kinds of data stores, such as key­value data stores, document­oriented data stores and graph databases. The reason why they have started to introduce this diversity of persistency models is because different NoSQL technologies bring different data models with associated query languages and/or APIs. However, they are confronted now with a problem in which they have the data scattered across different data stores. This problem lies in that when a business action requires to update the data, the data reside in different data stores, and they are subject to inconsistencies in the event of failure and/or concurrent access. These inconsistencies appear due to the lack of transactional consistency that was guaranteed in traditional SQL databases but is not guaranteed either within the NoSQL data stores or across data stores and databases. CoherentPaaS comes to remedy this need. CoherentPaaS provides an ultra­scalable transactional management layer that can be integrated with any data store with multi­ versioning capabilities. The layer has been integrated with six different data stores, three NoSQL data stores and three SQL­like databases. In this paper, we describe this generic ultra­scalable transactional management layer and focus on its API and how it can be integrated in different ways with different data stores and databases

A multi-resource load balancing algorithm for cloud cache systems

With the advent of cloud computing model, distributed caches have become the cornerstone for building scalable applications. Popular systems like Facebook [1] or Twitter use Memcached [5], a highly scalable distributed object cache, to speed up applications by avoiding database accesses. Distributed object caches assign objects to cache instances based on a hashing function, and objects are not moved from a cache instance to another unless more instances are added to the cache and objects are redistributed. This may lead to situations where some cache instances are overloaded when some of the objects they store are frequently accessed, while other cache instances are less frequently used. In this paper we propose a multi-resource load balancing algorithm for distributed cache systems. The algorithm aims at balancing both CPU and Memory resources among cache instances by redistributing stored data. Considering the possible conflict of balancing multiple resources at the same time, we give CPU and Memory resources weighted priorities based on the runtime load distributions. A scarcer resource is given a higher weight than a less scarce resource when load balancing. The system imbalance degree is evaluated based on monitoring information, and the utility load of a node, a unit for resource consumption. Besides, since continuous rebalance of the system may affect the QoS of applications utilizing the cache system, our data selection policy ensures that each data migration minimizes the system imbalance degree and hence, the total reconfiguration cost can be minimized. An extensive simulation is conducted to compare our policy with other policies. Our policy shows a significant improvement in time efficiency and decrease in reconfiguration cost

CumuloNimbo: A highly-scalable transaction processing platform as a service.

One of the main challenges facing next generation Cloud platform services is the need to simultaneously achieve ease of programming, consistency, and high scalability. Big Data applications have so far focused on batch processing. The next step for Big Data is to move to the online world. This shift will raise the requirements for transactional guarantees. CumuloNimbo is a new EC-funded project led by Universidad Politécnica de Madrid (UPM) that addresses these issues via a highly scalable multi-tier transactional platform as a service (PaaS) that bridges the gap between OLTP and Big Data applications

CumuloNimbo: a cloud scalable multi-tier SQL database

This article presents an overview of the CumuloNimbo platform. CumuloNimbo is a framework for multi-tier applications that provides scalable and fault-tolerant processing of OLTP workloads. The main novelty of CumuloNimbo is that it provides a standard SQL interface and full transactional support without resorting to sharding and no need to know the workload in advance. Scalability is achieved by distributing request execution and transaction control across many compute nodes while data is persisted in a distributed data store. In this paper we present an overview of the platform

Balancing multinational operations

SIGLEUuStB Koeln(38)-861100983 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

The mediating effect of trauma and stressor related symptoms and ruminations on the relationship between autistic traits and mood spectrum

An increasing number of studies highlighted significant correlations between autistic traits (AT) and mood spectrum symptoms. Moreover, recent data showed that individuals with high AT are likely to develop trauma and stressor-related disorders. This study aims to investigate the relationship between AT and mood symptoms among university students, focusing in particular on how AT interact with ruminations and trauma-related symptomatology in predicting mood symptoms. 178 students from three Italian Universities of excellence were assessed with The Structured Clinical Interview for DSM-5 (SCID-5), the Adult Autism Subthreshold Spectrum (AdAS Spectrum), the Ruminative Response Scale (RRS), the Trauma and Loss Spectrum (TALS) and the Moods Spectrum (MOODS). Considering the AdAS Spectrum total scores, 133 subjects (74.7%) were categorized as “low scorers” and 45 subjects (25.3%) as “high scorers”. Students in the high scorer group showed significantly higher scores on RRS, TALS-SR and MOOD-SR total scores. Total and direct effects of AdAS Spectrum total score on MOODS-SR total score were both statistically significant. AdAS Spectrum total score also showed a significant indirect effect on MOODS-SR total score through TALS and RRS total scores. Results showed a significant relationship between AT and mood spectrum, which is partially mediated by ruminations and trauma/stressor-related symptomatology

Catatonia Spectrum: Validation of a Questionnaire Investigating Catatonia Spectrum

AimA growing body of literature has demonstrated the utility of a dimensional perspective on mental disorders. The current study aims to determine the psychometric properties of the Catatonia Spectrum (CS), a new questionnaire specifically tailored to assess the spectrum of catatonia, from full blown forms to subthreshold ones. Methods86 adults with at least three symptom criteria for catatonia according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), 81 adults affected by borderline personality disorder (BPD), 104 adults with a diagnosis of major depressive disorder (MDD), and 105 subjects without mental disorders (CTL), were recruited from six Italian University Departments of Psychiatry and administered the: Bush-Francis Catatonia Rating Scale (BFCRS), Bush-Francis Catatonia Screening Instrument (BFCSI), and CS. ResultsCS scale demonstrated a high level of internal consistency and excellent test-retest reliability for total and domain scores. CS domain scores were positively and significantly correlated with each other (p < 0.001) with Pearson's coefficients ranging from 0.337 to 0.663. All the CS domain scores were highly correlated with the CS total score. The correlation coefficients between CS and alternative measures of catatonia appeared all significant and positive. Significant differences among diagnostic groups on both CS domains and total scores were found. CS total scores increased significantly and progressively from the CTL, to the MDD and the BDP group, up to the catatonia group, which reported the highest value. ConclusionThe CS showed excellent internal consistency and test-retest reliability and strong convergent validity with alternative dimensional measures of catatonia. The questionnaire performed differently across the four diagnostic groups, with an increasing score gradient from healthy controls to patients with MDD, BPD and up to the catatonia group

Investigating suicidality across the autistic-catatonic continuum in a clinical sample of subjects with major depressive disorder and borderline personality disorder

BackgroundRecent literature has highlighted that catatonia may be more prevalent among psychiatric patients than previously thought, beginning from autism spectrum disorders (ASD), for which it has been suggested to represent a severe late consequence, but also among individuals with mood disorders and borderline personality disorder (BPD). Interestingly, one critical point shared by these conditions is the increased risk of suicidality. The aim of this study was to evaluate how the presence and the prevalence of catatonic symptoms may shape and correlate with suicidal risk in a sample of individuals with major depressive disorder (MDD) or BPD.MethodsWe recruited two clinical samples of subjects (BPD and MDD) and a control group without a diagnosis according to DSM-5 (CTL). Subjects were assessed with the catatonia spectrum (CS) and the MOODS-SR for evaluating suicidality.ResultsIn the total sample, suicidality score was significantly and positively correlated with all CS domains and CS total score. Correlation and regression analyses highlighted specific patterns of association among Catatonia spectrum domains and suicidality in the MDD and BPD group and in the total sample.ConclusionIn both disorders, higher catatonic traits are linked to higher suicidal tendencies, confirming the high risk of suicide for this population. However, different patterns of association between catatonic symptoms and suicidality were highlighted in the two disorders