Explain task computing with it's diagram.

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 TASK COMPUTING

  • The most obvious and frequent method for developing parallel and distributed computing applications is an application in terms of tasks. A task denotes one or more processes that generate different outputs and may be separated as a distinct logical unit. A task is represented as a discrete unit of code, or to manage a program, which may be split and performed in a remote runtime environment. Programs are the most frequent way to express tasks, particularly in the field of scientific computing, which has benefited from the power of distributed computing.
  • Multithreaded programming is primarily concerned with enabling parallelism inside a single system. Task computing distributes compute power by utilizing the computation capabilities of several computing nodes. As a result, the presence of a distributed infrastructure is crucial in this programming paradigm. Previously, the infrastructures used to accomplish tasks have been clusters, supercomputers, and computing grids. Now, cloud computing has been established as an appealing approach for obtaining massive computing capacity on demand for the execution of distributed applications. It is required to use appropriate middleware software layers that helps to properly coordinate the use of multiple resources drawn from a data center or geographically distributed networked computers.


  • A user presents a group of tasks to the middleware's access point(s)/node(s), which will handle task scheduling and monitoring. Each computing resource offers a suitable runtime environment, which may differ from one implementation to the next (a simple shell, a sandboxed environment, or a virtual machine). The APIs supplied by the middleware, whether a Web or programming language interface, are often used for task submission. Appropriate APIs are also supplied to monitor task status and gather data when they are completed.
  • There are several models of distributed applications that fall under task computing. 

  • Despite this diversity, a set of common operations that the middleware needs to allow the design and execution of  task-based applications can be identified as:

  1. Coordination and scheduling of activities for execution on a collection of distant nodes 
  2. Transferring programs to remote nodes and maintaining their dependencies 
  3. Creating an environment for distant node task execution
  4. Monitoring each task's execution and alerting the user of its status
  5. Access to the task's output

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