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1

A novel adaptive checkpointing method based on information obtained from workflow structure

Kail E., Kacsuk P., Kozlovszky M.

Computer Science

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2016

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Vol. 17 (3)

387--406

EN

Scientific workflows are data- and compute-intensive; thus, they may run for days or even weeks on parallel and distributed infrastructures such as grids, supercomputers, and clouds. In these high-performance computing infrastruc- tures, the number of failures that can arise during scientific-workflow enact- ment can be high, so the use of fault-tolerance techniques is unavoidable. The most-frequently used fault-tolerance technique is taking checkpoints from time to time; when failure is detected, the last consistent state is restored. One of the most-critical factors that has great impact on the effectiveness of the checkpointing method is the checkpointing interval. In this work, we propose a Static (Wsb) and an Adaptive (AWsb) Workflow Structure Based checkpoint- ing algorithm. Our results showed that, compared to the optimal checkpointing strategy, the static algorithm may decrease the checkpointing overhead by as much as 33% without affecting the total processing time of workflow execution. The adaptive algorithm may further decrease this overhead while keeping the overall processing time at its necessary minimum.

2

Building science gateways by utilizing the generic WS-PGRADE/gUSE workflow system

Balasko A., Farkas Z., Kacsuk P.

Computer Science

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2013

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Vol. 14 (2)

307--325

EN

Enabling scientists to use remote distributed infrastructures, parametrize and execute common science-domain applications transparently is actual and a highly relevant field of distributed computing. For this purpose a general solution is the concept of Science Gateways. WS-PGRADE/gUSE system offers a transparent and web-based interface to access distributed resources (grids, clusters or clouds), extended by a powerful generic purpose workflow editor and enactment system, which can be used to compose scientific applications into data-flow based workflow structures. It’s a generic web-based portal solution to organize scientific applications in a workflow structure and execute them on remote computational resources. As the portal defines nodes as black-box applications uploaded by the users, it does not provide any application specific interface by default. In this paper we show what kind of tools, APIs and interfaces are available in WS-PGRADE/gUSE to customize it to have an application specific gateway.

3

Enabling generic distributed computing infrastructure compatibility for workflow management systems

Kozlovszky M., Karoczkai K., Marton I., Balasko A., Marosi A., Kacsuk P.

Computer Science

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2012

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Vol. 13 (3)

61-78

EN

Solving workflow management system’s Distributed Computing Infrastructure (DCI) incompatibility and their workflow interoperability issues are very challenging and complex tasks. Workflow management systems (and therefore their workflows, workflow developers and also their end-users) are bounded tightly to some limited number of supported DCIs, and efforts required to allow additional DCI support. In this paper we are specifying a concept how to enable generic DCI compatibility for grid workflow management systems (such as ASKALON, MOTEUR, gUSE/WS-PGRADE, etc.) on job and indirectly on workflow level. To enable DCI compatibility among the different workflow management systems we have developed the DCI Bridge software solution. In this paper we will describe its internal architecture, provide usage scenarios to show how the developed service resolve the DCI interoperability issues between various middleware types. The generic DCI Bridge service enables the execution of jobs onto the existing major DCI platforms (such as Service Grids (Globus Toolkit 2 and 4, gLite, ARC, UNICORE), Desktop Grids, Web services, or even cloud based DCIs).