A Study of Cloud/IX Operating System for the ARM-based Data Center Server Platform
Exponential growth in data production and a prominent trend in data center design architecture – a shift from expensive hardware towards a multitude of simple servers – pose new tasks and demand the use of different strategies for data center architects. In this work, a new solutions to distributed systems design are discussed, which are based on Plan9 operating system model. We first overview application and research projects including project of porting Plan9 to the IBM Blue Gene/L supercomputer, project of the Plan9 use in data centers and cloud systems, and projects aimed at distributed embedded systems. Then we introduce a Cloud/IX operating system for the ARM-based server platforms that also follows the Plan9 model and is implemented on top of one of Plan 9 derivatives called 9front - a free software distributed operating system. We also present the experimental testbed setup and results of experimental study of the Cloud/IX on multi-computer server farm in actual data center environment.
Proceedings of ISP RAS are a double-blind peer-reviewed journal publishing scientific articles in the areas of system programming, software engineering, and computer science. The journal's goal is to develop a respected network of knowledge in the mentioned above areas by publishing high quality articles on open access. The journal is intended for researchers, students, and practitioners.
This volume contains the papers presented at CS&P 2014: 23th International Workshop on Concurrency, Specification and Programming held on September 28 - October 1, 2014 in Chemnitz. Since the early seventies Warsaw University and Humboldt-University have alternately organized an annual workshop - since 1993 as CS&P. Over time, it has grown from a bilateral seminar to a meeting attended also by colleagues from other countries than Poland and Germany. This year there are 34 participants from 10 countries.
In the course of researching timetabling problems for complex distributed systems this article applies the multi-agent paradigm of computations and presents a correspondent mathematical model for university’s timetabling problem solution. The model takes into account dynamic nature of this problem and individual preferences of different remote users for time and location of classes. In the framework of that model authors propose an original problem-oriented algorithm of multi-agent communication. Developed algorithm is used as a foundation for the distributed software system AgentTime. Based on multi-agent JADE platform AgentTime provides friendly graphical interface for online design of time tables for universities.
A novel approach to solving the nearest neighbor search problem in metric space is considered. It is proposed as a data structure to use a graph with navigable small world properties and a gradient descent algorithm as a search algorithm. The problem of the existence of local minima is solved by a series of independent searches. Experimental data are presented to confirm logarithmic complexity of the search algorithm.
The paper considers an existent data centers safety categories and power usage effectiveness. Few type of data centers organization reviewed. Some example of modern scientific data center presented. It has been shown that most of the scientific data centers are built for specific tasks.
Immense volumes of geospatial arrays are generated daily. Examples of such include satellite imagery, numerical simulation, and derivative dataavalanche. Array DBMS are one of the prominent tools for working with large geospatial arrays. Usually the arrays natively come as raster files. ChronosDB is a novel distributed, file based, geospatial array DBMS: chronosdb.gis.land . ChronosDB operates directly on raster files, delegates array processing to existing elaborate command line tools, and outperforms SciDB by up to 75 × on average. This demonstration will showcase three new components of ChronosDB enabling users to interact with the system and appreciate its benefits: (i) a WebGUI (edit, submit queries and get the output), (ii) an execution plan explainer (investigate the generated DAG), and (iii) a dataset visualizer (display ChronosDB arrays on an interactive web map).
The article describes the results of the analysis of the traffic of the inromational and computational resources connected to the Moscow region research telecommunication network of the Russian Academy of Sciences. Based on the analysis the demands for data-center connectivity were considered. Reliable and high-performance network architecture solutions were proposed. The prototype of the telecommunication node for data-center connectivity is developed in the Computational Center of the Russian Academy of Sciences.
18th Conference on Plasma-Surface Interactions, PSI 2015, 5-6 February 2015, Moscow, Russian Federation and the 1st Conference on Plasma and Laser Research and Technologies, PLRT 2015, 18-20 February 2015
A model for organizing cargo transportation between two node stations connected by a railway line which contains a certain number of intermediate stations is considered. The movement of cargo is in one direction. Such a situation may occur, for example, if one of the node stations is located in a region which produce raw material for manufacturing industry located in another region, and there is another node station. The organization of freight traﬃc is performed by means of a number of technologies. These technologies determine the rules for taking on cargo at the initial node station, the rules of interaction between neighboring stations, as well as the rule of distribution of cargo to the ﬁnal node stations. The process of cargo transportation is followed by the set rule of control. For such a model, one must determine possible modes of cargo transportation and describe their properties. This model is described by a ﬁnite-dimensional system of diﬀerential equations with nonlocal linear restrictions. The class of the solution satisfying nonlocal linear restrictions is extremely narrow. It results in the need for the “correct” extension of solutions of a system of diﬀerential equations to a class of quasi-solutions having the distinctive feature of gaps in a countable number of points. It was possible numerically using the Runge–Kutta method of the fourth order to build these quasi-solutions and determine their rate of growth. Let us note that in the technical plan the main complexity consisted in obtaining quasi-solutions satisfying the nonlocal linear restrictions. Furthermore, we investigated the dependence of quasi-solutions and, in particular, sizes of gaps (jumps) of solutions on a number of parameters of the model characterizing a rule of control, technologies for transportation of cargo and intensity of giving of cargo on a node station.
Event logs collected by modern information and technical systems usually contain enough data for automated process models discovery. A variety of algorithms was developed for process models discovery, conformance checking, log to model alignment, comparison of process models, etc., nevertheless a quick analysis of ad-hoc selected parts of a journal still have not get a full-fledged implementation. This paper describes an ROLAP-based method of multidimensional event logs storage for process mining. The result of the analysis of the journal is visualized as directed graph representing the union of all possible event sequences, ranked by their occurrence probability. Our implementation allows the analyst to discover process models for sublogs defined by ad-hoc selection of criteria and value of occurrence probability
The geographic information system (GIS) is based on the first and only Russian Imperial Census of 1897 and the First All-Union Census of the Soviet Union of 1926. The GIS features vector data (shapefiles) of allprovinces of the two states. For the 1897 census, there is information about linguistic, religious, and social estate groups. The part based on the 1926 census features nationality. Both shapefiles include information on gender, rural and urban population. The GIS allows for producing any necessary maps for individual studies of the period which require the administrative boundaries and demographic information.
Existing approaches suggest that IT strategy should be a reflection of business strategy. However, actually organisations do not often follow business strategy even if it is formally declared. In these conditions, IT strategy can be viewed not as a plan, but as an organisational shared view on the role of information systems. This approach generally reflects only a top-down perspective of IT strategy. So, it can be supplemented by a strategic behaviour pattern (i.e., more or less standard response to a changes that is formed as result of previous experience) to implement bottom-up approach. Two components that can help to establish effective reaction regarding new initiatives in IT are proposed here: model of IT-related decision making, and efficiency measurement metric to estimate maturity of business processes and appropriate IT. Usage of proposed tools is demonstrated in practical cases.
Let G be a semisimple algebraic group whose decomposition into the product of simple components does not contain simple groups of type A, and P⊆G be a parabolic subgroup. Extending the results of Popov , we enumerate all triples (G, P, n) such that (a) there exists an open G-orbit on the multiple flag variety G/P × G/P × . . . × G/P (n factors), (b) the number of G-orbits on the multiple flag variety is finite.
I give the explicit formula for the (set-theoretical) system of Resultants of m+1 homogeneous polynomials in n+1 variables