Zeek_69_Multiprocessing And Multithreading in Java

 

What is a thread in Java?

A thread is a lightweight sub-process, the smallest unit of processing.

Why are multiprocessing and multithreading used in Java?

Multiprocessing and multithreading,  both are used to achieve multitasking.

Multitasking(It is the concurrent execution of multiple tasks over a certain period of time.)

What is multithreading and multiprocessing in Java and     which one is more convenient?

Multithreading  is a programming language concept in which a program or process is divided into two or more subprograms that are executed at the same time in parallel.

In other words

 Multithreading is a program execution technique that allows a single process to have multiple code segments (like threads). 

Whereas....

Multiprocessing refers to using multiple CPUs/processors in a single system.

 Multiple CPUs can act in a parallel fashion and executes multiple processes together. 

They increase computing power to a great extent. 

Symmetric multiprocessing and asymmetric multiprocessing are two types of multiprocessing.

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However, we use multithreading usually more than multiprocessing because threads use a shared memory area. They don't allocate separate memory area so saves memory, and context-switching between the threads takes less time than process.

Java Multithreading is mostly used in games, animation, etc.

Multitasking

Multitasking is a process of executing multiple tasks simultaneously. We use multitasking to utilize the CPU. Multitasking can be achieved in two ways:

• Process-based Multitasking (Multiprocessing)
• Thread-based Multitasking (Multithreading)

1) Process-based Multitasking (Multiprocessing)

• Each process has an address in memory. In other words, each process allocates a separate memory area.
• A process is heavyweight.
• Cost of communication between the process is high.
• Switching from one process to another requires some time for saving and loading registers
  , memory maps, updating lists, etc.

2) Thread-based Multitasking (Multithreading)

• Threads share the same address space.
• A thread is lightweight.
• Cost of communication between the thread is low.