Here are some key points that we need to consider before starting using the Parallel Streams:
Use Parallel Streams if:
- You have a massive amount of items to process (or the processing of each item takes time)
You have a performance issue in the first place
You are certain that there will be an actual benefit to the performance of the application
You determined that splitting is not more expensive than just doing the work
You know that you have a few CPU threads that are free to use
You are not interested in the order of execution
You have good reason to believe that it will preserve the correctness of the computation
- You know that the data you are going to split is easy to decompose
When replacing the regular Streams with Parallel Streams in big applications, you must ensure first that doing this will not break anything. Use regression testing tools to check for any errors.
You see, to use them, you must first do deep research into whether this new approach will suit your application. For example, does your machine have enough capacity to support it? What is the data you are working with?
Is it a simple collection, such as ArrayList or an array? Or a LinkedList, which takes a long time to split.
You need to think carefully about these things and many more before using Parallel Streams.