OCR A Level CS 2.1.5 CS Thinking Concurrently

What is concurrent thinking?

The ability to identify parts of a problem that can be solved at the same time.

How is concurrent thinking different from concurrent processing?

Concurrent thinking happens in the brain, while concurrent processing happens in a computer.

Give an example of concurrent thinking.

Recording both the number plate and colour of passing cars instead of recording them separately.

What is concurrent processing?

When a processor switches between multiple tasks, giving the illusion of simultaneous execution.

How does concurrent processing work?

Tasks are given small time slices of processor time, making them appear simultaneous.

How is concurrent processing different from parallel processing?

• Concurrent processing → One processor switching between tasks.

• Parallel processing → Multiple processors executing tasks at the same time.

How can you determine if a task can be processed concurrently?

Identify if tasks are independent or have dependencies on other tasks.

When is concurrency not useful?

When tasks rely on previous steps (e.g., a recipe where ingredients must be added in a specific order).

What are the main benefits of concurrent processing?

✅ More tasks completed in a given time.
✅ Less idle time (e.g., while waiting for input, another task can run).
✅ Better system efficiency and resource utilization.

What are the drawbacks of concurrent processing?

❌ Increased overhead from managing multiple tasks.
❌ Longer execution time when too many tasks compete for processor time.
❌ Some tasks cannot be broken down into smaller concurrent parts.