ATOM: model-driven autoscaling for microservices

Microservices based architectures are increasinglywidespread in the cloud software industry. Still, there is ashortage of auto-scaling methods designed to leverage the uniquefeatures of these architectures, such as the ability to indepen-dently scale a subset of microservices, as well as the ease ofmonitoring their state and reciprocal calls.We propose to address this shortage with ATOM, a model-driven autoscaling controller for microservices. ATOM instanti-ates and solves at run-time a layered queueing network model ofthe application. Computational optimization is used to dynami-cally control the number of replicas for each microservice and itsassociated container CPU share, overall achieving a fine-grainedcontrol of the application capacity at run-time.Experimental results indicate that for heavy workloads ATOMoffers around 30%-37% higher throughput than baseline model-agnostic controllers based on simple static rules. We also find thatmodel-driven reasoning reduces the number of actions needed toscale the system as it reduces the number of bottleneck shiftsthat we observe with model-agnostic controllers

Is depression a real risk factor for acute myocardial infarction mortality? A retrospective cohort study

Background: Depression has been associated with a higher risk of cardiovascular events and a higher mortality in patients with one or more comorbidities. This study investigated whether continuative use of antidepressants (ADs), considered as a proxy of a state of depression, prior to acute myocardial infarction (AMI) is associated with a higher mortality afterwards. The outcome to assess was mortality by AD use. Methods: A retrospective cohort study was conducted in the Veneto Region on hospital discharge records with a primary diagnosis of AMI in 2002-2015. Subsequent deaths were ascertained from mortality records. Drug purchases were used to identify AD users. A descriptive analysis was conducted on patients' demographics and clinical data. Survival after discharge was assessed with a Kaplan-Meier survival analysis and Cox's multiple regression model. Results: Among 3985 hospital discharge records considered, 349 (8.8%) patients were classified as AD users'. The mean AMI-related hospitalization rate was 164.8/100,000 population/year, and declined significantly from 204.9 in 2002 to 130.0 in 2015, but only for AD users (-40.4%). The mean overall follow-up was 4.64.1years. Overall, 523 patients (13.1%) died within 30days of their AMI. The remainder survived a mean 5.3 +/- 4.0years. After adjusting for potential confounders, use of antidepressants was independently associated with mortality (adj OR=1.75, 95% CI: 1.40-2.19). Conclusions: Our findings show that AD users hospitalized for AMI have a worse prognosis in terms of mortality. The use of routinely-available records can prove an efficient way to monitor trends in the state of health of specific subpopulations, enabling the early identification of AMI survivors with a history of antidepressant use

Tri nove vrste i jedan novi rod ultraspecijaliziranih špiljskih leptodirina iz Hrvatske (Coleoptera, Cholevidae)

Croatodirus casalei Giachino & Jalžić, new species from N Velebit, Lubenovac, Slovačka jama pothole, and C. ozimeci Casale, Giachino & Jalžić new species, from Lokve, Lokvarka špilja cave, are described. The morphological features of the new taxa are compared with those of the type species of the genus (C. bozicevici Casale, Giachino & Jalžić, 2000). The genus is confirmed as a homogeneous, well characterized and monophyletic unit, and is attributed to the phyletic lineage of Anthroherpon. Velebitodromus, new genus, smidai new species, is described from N Velebit, Lubenovac, Mali kuk, Slovačka jama pothole. Owing to both external features and structures of male and female genitalia, the genus is attributed to the phyletic lineage of Anthroherpon, and is recognized as related to the genera Anthroherpon Reitter, 1889, and Paranthrophilon Reitter, 1889.U radu su opisane Croatodirus casalei Giachino & Jalžić, nova vrsta sa Sjevernog Velebita (Lubenovac, Mali kuk, Slovačka jama) i C. ozimeci Casale, Giachino & Jalžić, nova vrsta iz Lokava (špilja Lokvarka). Njihova morfološka svojstva uspoređuju se s onima tipske vrste ovog roda (C. bozicevici Casale, Giachino & Jalžić, 2000). Rod se potvrđuje kao homogen, jasno raspoznatljiv i monofiletički, te je pridodan filetičkoj liniji Anthroherpon. Novi rod Velebitodromus s novom vrstom smidai opisan je također sa Sjevernog Velebita (Lubenovac, Slovačka jama). Zbog vanjskih osobina i zbog građe muških i ženskih genitalija, rod je pridodan filetičkoj liniji Anthroherpon, i prepoznaje se kao srodan rodovima Anthroherpon Reitter, 1889 i Paranthrophilon Reitter, 1889

QMLE: a methodology for statistical inference of service demands from queueing data

Estimating the demands placed by services on physical resources is an essential step for the definition of performance models. For example, scalability analysis relies on these parameters to predict queueing delays under increasing loads. In this paper, we investigate maximum likelihood (ML) estimators for demands at load-independent and load-dependent resources in systems with parallelism constraints. We define a likelihood function based on state measurements and derive necessary conditions for its maximization. We then obtain novel estimators that accurately and inexpensively obtain service demands using only aggregate state data. With our approach, and also thanks to approximation methods for computing marginal and joint distributions for the load-dependent case, confidence intervals can be rigorously derived, explicitly taking into account both topology and concurrency levels of the services. Our estimators and their confidence intervals are validated against simulations and real system measurements for two multi-tier applications, showing high accuracy also in the presence of load-dependent resources

Responsive Urban Models by Processing Sets of Heterogeneous Data

This paper presents some steps in experimentation aimed at describing urban spaces made following the series of earthquakes that affected a vast area of central Italy starting on 24 August 2016. More specifically, these spaces pertain to historical centres of limited size and case studies that can be called "problematic" (due to complex morphological and settlement conditions, because they are difficult to access, or because they have been affected by calamitous events, etc.). The main objectives were to verify the use of sets of heterogeneous data that are already largely available to define a workflow and develop procedures that would allow some of the steps to be automated as much as possible. The most general goal was to use the experimentation to define a methodology to approach the problem aimed at developing descriptive responsive models of the urban space, that is, morphological and computer-based models capable of being modified in relation to the constantly updated flow of input data

Flora and Fauna in East Asian Art

Flora and Fauna in East Asian Art is the fourth annual exhibition curated by students enrolled in the Art History Methods course. This exhibition highlights the academic achievements of six student curators: Samantha Frisoli ’18, Daniella Snyder ’18, Gabriella Bucci ’19, Melissa Casale ’19, Keira Koch ’19, and Paige Deschapelles ’20. The selection of artworks in this exhibition considers how East Asian artists portrayed similar subjects of flora and fauna in different media including painting, prints, embroidery, jade, and porcelain. This exhibition intends to reveal the hidden meanings behind various representations of flora and fauna in East Asian art by examining the iconography, cultural context, aesthetic and function of each object.https://cupola.gettysburg.edu/artcatalogs/1025/thumbnail.jp

Ground-based NO2 measurements at the Italian Brewer stations: A pilot study with Global Ozone Monitoring Experiment (GOME)

Ground-based NO2 total column measurements have been collected since 1992 using Brewer spectrophotometry at Rome, an urban site, and Ispra (semirural). These are the only ground-based stations regularly monitoring NO2 in Italy. The methodology of measurement together with the procedure to control its quality is described. From the analysis of the time series it was found that the mean value of the NO2 column is 1.63 DU atRome and 1.60 DU atIspra. A firstat tempt to compare NO2 vertical column densities (VCD) from GOME with those derived from ground-based Brewer measurements, under different atmospheric conditions and measurement time lags is here presented. The results of this pilot study showed unsatisfactory agreement because different atmospheres are probed by GOME and Brewer instruments. The GOME space resolution resulted insufficient to fully characterize the Rome and Ispra highly localized polluted areas

Ground-based NO2 measurements at the Italian Brewer stations: A pilot study with Global Ozone Monitoring Experiment (GOME)

Ground-based NO2 total column measurements have been collected since 1992 using Brewer spectrophotometry at Rome, an urban site, and Ispra (semirural). These are the only ground-based stations regularly monitoring NO2 in Italy. The methodology of measurement together with the procedure to control its quality is described. From the analysis of the time series it was found that the mean value of the NO2 column is 1.63 DU atRome and 1.60 DU atIspra. A firstat tempt to compare NO2 vertical column densities (VCD) from GOME with those derived from ground-based Brewer measurements, under different atmospheric conditions and measurement time lags is here presented. The results of this pilot study showed unsatisfactory agreement because different atmospheres are probed by GOME and Brewer instruments. The GOME space resolution resulted insufficient to fully characterize the Rome and Ispra highly localized polluted areas

A macroscale hydrogeological numerical model of the Suio hydrothermal system (Central Italy)

The complex behaviour of the Suio hydrothermal system (central Italy) and its potential exploitation as a renewable energy source are still unclear. To quantitatively evaluate the geothermal resource, the Suio hydrothermal system has been investigated with a hydrogeological numerical model that couples fluid flow, thermal convection, and transport of diluted species inside a hybrid continuum-discrete medium. The numerical model, calibrated and validated with available and new experimental data, unveiled the complex behaviour of the hydrothermal system. The normal tectonic displacements, the fracturing of the karst hydrostructure, and the aquitard distribution strongly influence the hydrothermal basin. In particular, a dual fluid circulation, sustained by steady-state thermal and pressure gradients, modulates the hydrothermalism at the several springs and wells. The presence of a medium to a low-temperature reservoir allows for potential exploitation of the geothermal resource

Performance engineering for microservices and serverless applications: the RADON approach

Microservices and serverless are becoming integral parts of mod-ern cloud-based applications. Tailored performance engineering isneeded for assuring that the applications meet their requirementsfor quality attributes such as timeliness, resource efficiency, andelasticity. A novel DevOps-based framework for developing mi-croservices and serverless applications is being developed in theRADON project. RADON contributes to performance engineeringby including novel approaches for modeling, deployment optimiza-tion, testing, and runtime management. This paper summarizes thecontents of our tutorial presented at the 11th ACM/SPEC Interna-tional Conference on Performance Engineering (ICPE)