Multithreading concurrent parallel threaded process

Multithreading

Concurrent ： Two or more events occur in the same time period . parallel ： Two or more events occur at the same time （ At the same time ）.

process ： A running application is a process . Threads ： Is an execution unit of a process . A process has at least one thread , There can be multiple threads , Such programs are called multithreaded programs .

Process diagram ：

Thread diagram ：

Thread scheduling ：

1. Time sharing scheduling ： All threads rotate CPU Right to use , Average per thread CPU Time for . 2. preemptive scheduling ： Give priority to high priority threads CPU, If the priority is the same , Then choose one at random （ Thread randomness ）,Java Preemptive scheduling is used .