Sandbox Concepts and Terminology » History » Version 3
Herve Caumont, 2013-06-18 16:11
| 1 | 1 | Herve Caumont | h1. Sandbox Concepts and Terminology |
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| 3 | {{>toc}} |
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| 5 | h2. Concepts |
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| 7 | h3. Directed Acyclic Graph (DAG) |
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| 9 | In mathematics and computer science, a Directed Acyclic Graph (DAG), is a directed graph with no directed cycles. DAGs may be used to model several different kinds of structure. By definition a DAG is a directed graph with no path that starts and ends at the same vertex. |
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| 10 | This notion is in place in distributed processing flows and used in ESA EO toolboxes such as BEAM and NeST. |
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| 11 | The CCBox uses the DAG to describe the science application +*workflow+*. |
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| 13 | h2. Terminology |
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| 15 | h3. Task |
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| 17 | To exploit the parallelism offered by the framework, a +*job+* may process its input in several tasks. In principle, the framework runs the tasks in parallel within a +*job*+. |
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| 18 | A +*job+* can then have one or more +*tasks*+. |