Parallel processing

<aside> 💡 With the existence of multicore processors, we need software that is able to utilise this power

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• More than one processing unit works on a single task, sharing the load of the processing power required
• To do this, the single task is split into smaller 'chunks' called threads, and these are assigned to each individual processing unit, which execute the thread immediately
• Both units need to communicate with each other to ensure that they always have the most up-to-date piece of data to work with
• Calculations are carried simultaneously
• Operates on the principle that large problems can often be divided into smaller ones, which are then solved concurrently

✅  Advantages

• Faster execution, as more instructions run in a shorter time span
• Each task is equally shared, so no processing unit will be more loaded than the others

❌  Disadvantages

• Much more difficult to write programs that take advantage of a multi-core system
• Data must be up-to-date, and processing units will need to change their calculations based on the actions of other processing units
• Cannot split sequential tasks
• Concurrency (multiple computations happening at the same time) means more software bugs to deal with
• Communication and synchronisation between the different subtasks are typically some of the greatest obstacles to getting efficient parallel program performance

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