2.1.5 Thinking concurrently

• Concurrent thinking


  The process of completing more than one task at a given time
• Concurrent thinking does not always mean you have to be working on multiple tasks at once
• Concurrent thinking


  Involves giving 'slices' of your time to different tasks
• Parts of a problem which are related can often be solved concurrently
• Concurrent processing


  Not the same as parallel processing
• Parallel processing


  Multiple processors are used to complete more than one task simultaneously
• Concurrent processing


  Each task is given a slice of processor time to make it appear as if tasks are being completed simultaneously
• In reality, tasks are executed sequentially in concurrent processing
• Benefits of concurrent processing

  • The number of tasks completed in a given time is increased
  • Less time is wasted waiting for an input or user interaction, as other tasks can be completed in this time
• Drawbacks of concurrent processing

  • Concurrent processing can take longer to complete when large numbers of users or tasks are involved as processes cannot be completed at once
  • There is an overhead in coordinating and switching between processes, which reduces program throughput
  • Not all tasks are suited to being broken up and performed concurrently