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Policy-based sla storagemanagement model fordistributeddata storage services

Nikolow D., Słota R., Polak S., Pogoda M., Kitowski J.

Computer Science

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2018

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Vol. 19 (4)

403--429

EN

There is high demand for storage related services supporting scientists in their research activities. Those services are expected to provide not only capacity but also features allowing for more exible and cost ecient usage. Such features include easy multiplatform data access, long term data retention, support for performance and cost dierentiating of SLA restricted data access. The paper presents a policy-based SLA storage management model for distributed data storage services. The model allows for automated management of distributed data aimed at QoS provisioning with no strict resource reservation. The problem of providing users with the required QoS requirements is complex, and therefore the model implements heuristic approach for solving it. The corresponding system architecture, metrics and methods for SLA focused storage management are developed and tested in a real, nationwide environment. Keywords distributed storage systems, quality of service, service level agreement, management model, heuristics.

2

Management methods in SLA-aware distributed storage systems

Nikolow D., Słota R., Lakovic D., Winiarczyk P., Pogoda M., Kitowski J.

Computer Science

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2012

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Vol. 13 (3)

35-44

EN

Traditional data storage systems provide access to user’s data on the "best effort" basis. While this paradigm is sufficient in many use cases it becomes an obstacle for applications with Quality of Service (QoS) constraints. Service Level Agreement (SLA) is a part of the contract agreed between the service provider and the client and contains a set of well defined QoS requirements regarding the provided service and the penalties applied in case of violations. In the paper we propose a set of SLA parameters and QoS metrics relevant to data storage processes and the management methods necessary for avoiding SLA violations. A key assumption in the proposed approach is that the underlying distributed storage system does not provide functionality for resource or bandwidth reservation for a given client request.

3

A toolkit for storage QoS provisioning for data-intensive applications

Słota R., Król D., Skałkowski K., Orzechowski M., Nikolow D., Kryza B., Wrzeszcz M., Kitowski J.

Computer Science

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2012

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Vol. 13 (1)

63-73

EN

This paper describes a programming toolkit developed in the PL-Grid project, named QStorMan, which supports storage QoS provisioning for data-intensive applications in distributed environments. QStorMan exploits knowledgeoriented methods for matching storage resources to non-functional requirements, which are defined for a data-intensive application. In order to support various usage scenarios, QStorMan provides two interfaces, such as programming libraries or a web portal. The interfaces allow to define the requirements either directly in an application source code or by using an intuitive graphical interface. The first way provides finer granularity, e.g., each portion of data processed by an application can define a different set of requirements. The second method is aimed at legacy applications support, which source code can not be modified. The toolkit has been evaluated using synthetic benchmarks and the production infrastructure of PL-Grid, in particular its storage infrastructure, which utilizes the Lustre file system.

4

Performance aspects of data delivery using hierarchical storage management systems in the grid

Nikolow D., Słota R., Kitowski J.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2004

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Vol. 8, No 4

537-548

EN

Grid computing has recently gained in popularity. Grid applications can be very demanding of the data storage facilities in the Grid. The existing data grid services are often insufficient and additional optimization of the data access is necessary. This paper presents research concerning the optimization aspects of data management for Hierarchical Storage Management (HSM) systems in the Grid.

5

Large scale computing as a vehicle for studies in computational and computer sciences

Kitowski J., Alda W., Boryczko K., Bubak M., Dzwinel W., Funika W., Mościński J., Nikolow D., Pogoda M., Słota R., Wcisło R

Zeszyty Naukowe Uniwersytetu Jagiellońskiego. Prace Informatyczne

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2000

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z. 10

51-68

EN

In this paper we present some methods and algorithms for large scale computing which cover different areas of computational and computer sciences. They concern particle models, CFD computing, animation, monitoring and predicting of application performance as well as scientific visualization and scientific data storing and retrieving.

6

Multimedia information systems for long-distance cooperation in medicine

Słota R., Kitowski J., Polak S., Nikolow D., Otfinowski J.

Journal of Medical Informatics & Technologies

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2000

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Vol. 1

IT 107--112

EN

The authors of this paper take part in research on Distributed Medical Information System in the framework of the PARMED project. We cooperate with a clinic which possesses large stuff of medical image and video data. In order to share this valuable material with other similar institutions for scientific and educational purposes, we provide a large virtual database of medical video and image data, rather than video-conferencing or using medical video and image data within decision support for single patient’s diagnostics. The meta-database is the central component of the PARMED system. It maps user queries onto the physical address (URL) of the required data. This is made possible by adding annotations to images and videos. This paper presents two subsystems of the PARMED project: Multimedia Storage and Retrieval System (MMSRS) and Supporting Tool for Teleeducation (SULED). Multimedia Storage and Retrieval System is aimed at storing and retrieving medical multimedia data such as images and videos. Tertiary storage is required for MMSRS because the volume of the video material cannot be stored economically on magnetic disks. The system consists of Automated Media Library (AML) and the following software components: AML managing system (UniTree Hierarchical Storage Management – the commercial software), MPEG Extension for HSM (MEH) and a public domain WWW server. In order to workaround the difficulties connected with the UniTree HSM functionality, we decided to cut the videos into pieces of similar size and store them as different files. The cutting substantially reduces the start-up delay. MEH is written in C and uses the Common Gateway Interface (CGI) to communicate with the WWW server. No QoS guarantee could be maintained with the MMSRS, therefore a strategy of the video server and MMSRS cooperation is being developed. The second approach to build MMSRS, that we have started to investigate, is an attempt to build a specialized AML management system from scratch. For educational purposes we have defined a lecture or a course as a set of presentation material consisting of multimedia information, logically organized by a lecturer, and presented electronically to participants. The presentation is assembled with data already introduced into PARMED system (and typically existing on MMSRS). Besides the physical data from medical cases, some written material like slides with text and other graphical objects are also considered. At our institute there has been undertaken creation of the semi-automatic tools for preparation of lectures and courses which could support lecturers. One of them is SULED (Supporting Tool for Teleeducation). Pictures (gif/jpeg) are the source for SULED and can contain the active areas. When one clicks or moves over the area, the proper action is performed. The action can be: starting a movie, opening a new page, etc. SULED returns the presentation as a sequence of the WWW pages, so this presentation can be viewed by the WWW browsers. Nowadays a new tool called MULTI is being created. MULTI implements the idea of SULED and makes it possible to create the multimedia lectures. The lecture contains blocks of: pictures, sounds, movies, texts. These blocks can communicate and, for example, when viewing a movie text information can be displayed. These information will be synchronized with the contents of the movie.

PL

W niniejszej pracy przedstawiono prace badawcze podjęte w Zespole Katedry Informatyki Akademii Górniczo – Hutniczej umożliwiające tworzenie systemów informatycznych dla współpracy na duże odległości w zakresie efektywnego wykorzystywania danych multimedialnych. Celem tych prac jest zaprojektowanie, zaimplementowanie i zbadanie rozproszonego systemu informatycznego do współpracy na duże odległości obejmującego pozyskiwanie, przechowywanie, przetwarzanie i udostępnianie multimedialnych danych na przykładzie danych medycznych.