Browsing by Subject "scalability"

Now showing 1 - 9 of 9

Access status: Open Access ,
An agent-based hierarchical approach for executing bag-of-tasks in clouds
(Wydawnictwa AGH, 2014) Funika, Włodzimierz; Mazurek, Kamil; Kruczkowski, Wojciech
Unlike message-passing applications, »bag-of-tasks« applications (BoTs), whose tasks are unrelated and independent (no inter-task communication), can be highly parallelized and executed in any acceptable order. A common practice when executing bag-of-tasks applications (BoT) is to exploit the master-slave topology. Cloud environments offer some features that facilitate the execution of BoT applications. One of the approaches to control-cloud resources is to use agents that are flexible actors in a dynamic environment. Given these assumptions, we have designed a combination of approaches which can be classified as distributed, hierarchical solutions to the issue of scalable execution of bag-of-tasks. The concept of our system relates to a project that is focused on processing huge quantities of incoming data from a network of sensors through the Internet. Our aim is to create a mechanism for processing such data as a system that executes jobs while exploiting load balancing for cloud resources which use applications such as Eucalyptus. The idea is to create a hybrid architecture which takes advantage of some centralized parts of the system and full distributedness in other parts. On the other hand, we balance dependencies between system components using a hierarchical master-slave structure.
Access status: Open Access ,
Desynchronization of simulation and optimization algorithms in HPC environment
(Wydawnictwa AGH, 2020) Starzec, Mateusz; Starzec, Grażyna; Paciorek, Mateusz
The need for the scalability of an algorithm is essential when one wants to utilize an HPC infrastructure in an efficient and reasonable way. In such infrastructures, synchronization affects the efficiency of the parallel algorithms. However, one can consider introducing certain means of desynchronization in order to increase the scalability. Allowing certain messages to be omitted or delayed can be easily accepted in the case of metaheuristics. Furthermore, some simulations can also follow this pattern and thereby handle bigger environments. The paper presents a short survey on the desynchronization idea, pointing out already obtained results, or sketching out future work focused on scaling the parallel and distributed computing or simulation algorithms.
Access status: Open Access ,
Efficient simulations of large-scale convective heat transfer problems
(Wydawnictwa AGH, 2021) Goik, Damian; Banaś, Krzysztof; Bielański, Jan Gustaw; Chłoń, Kazimierz
We describe an approach for efficient solution of large-scale convective heat transfer problems that are formulated as coupled unsteady heat conduction and incompressible fluid-flow equations. The original problem is discretized over time using classical implicit methods, while stabilized finite elements are used for space discretization. The algorithm employed for the discretization of the fluid-flow problem uses Picard’s iterations to solve the arising nonlinear equations. Both problems (the heat transfer and Navier–Stokes equations) give rise to large sparse systems of linear equations. The systems are solved by using an iterative GMRES solver with suitable preconditioning. For the incompressible flow equations, we employ a special preconditioner that is based on an algebraic multigrid (AMG) technique. This paper presents algorithmic and implementation details of the solution procedure, which is suitably tuned – especially for ill-conditioned systems that arise from discretizations of incompressible Navier–Stokes equations. We describe a parallel implementation of the solver using MPI and elements from the PETSC library. The scalability of the solver is favorably compared with other methods, such as direct solvers and the standard GMRES method with ILU preconditioning.
Access status: Restricted ,
Projekt i implementacja skalowalnego backendu dla platformy społecznościowej
(Data obrony: 2017-01-24) Smoczyński, Karol
Wydział Elektrotechniki, Automatyki, Informatyki i Inżynierii Biomedycznej
Access status: Restricted ,
Scalable architecture of cloud application based on CQRS and Event Sourcing
(Data obrony: 2015-09-30) Dębski, Andrzej; Szczepanik, Bartłomiej
Wydział Informatyki, Elektroniki i Telekomunikacji
Access status: Restricted ,
Scalable architecture of cloud application based on CQRS and Event Sourcing
(Data obrony: 2015-09-30) Szczepanik, Bartłomiej; Dębski, Andrzej
Wydział Informatyki, Elektroniki i Telekomunikacji
Access status: Restricted ,
Tracing of Large-scale Actor Systems
(Data obrony: 2017-07-14) Ciołczyk, Michał
Wydział Informatyki, Elektroniki i Telekomunikacji
Access status: Restricted ,
Tworzenie skalowalnych serwisów internetowych
(Data obrony: 2010-07-07) Hajduk, Adrian
Wydział Geologii, Geofizyki i Ochrony Środowiska
A load balancing issue for homogeneous and heterogeneous web servers is described in this document. The review of algorithms and solutions is shown. The independence of simultaneous requests for this server is proved. Results of experimental tests are presented.
Access status: Restricted ,
Tworzenie skalowalnych systemów informatycznych w oparciu o Cloud Computing
(Data obrony: 2013-07-04) Habrat, Krzysztof
Wydział Geologii, Geofizyki i Ochrony Środowiska
In this paper, a load balancing issue for Cloud Computing based web servers was described. Author made review of the most popular (commercial and noncommercial) Cloud Computing systems. The EUCALYPTUS cloud and its use for parallel processing for web services was presented. The review of three load balancing algorithms (Request Counting, Weighted Traffic Counting and Pending Request Counting) was shown.