First, the process
Liu big fat turn on the computer and want to write something, then open the WPS, and suddenly want a girlfriend (I do not believe anyway) chat, and again opened the micro-channel PC side, then the operating system will generate two for the two programs a process, as shown:
Second, thread
Each process contains at least one thread, the thread is a basic unit of scheduling and execution of the CPU, may be received while the WPS text input, while automatically saved, then there will be two processes, as shown:
Third, concurrent
Liu Taipan entered in the WPS text, the program automatically saves, but did not appear Caton, because the CPU uses time-slicing in the implementation of multi-threading, because the CPU changes very fast, Liu did not feel Taipan card, In fact, a certain point of time on the CPU will only execute one thread, the thread switching multiple concurrent execution is called, as shown:
Fourth, parallel
Liu Tai Pan recently upgraded the computer's CPU, rose from a two nuclear core, multi-threaded execution so when the CPU can execute the two nuclear one, which is parallel, as shown:
V. Summary
- Process: In fact, the operating system is an abstraction of a running program is
- Thread: A thread is the smallest unit of CPU scheduling is to ensure that multi-task in a thread
- Concurrency: a CPU core to execute multiple threads by switching time
- Parallel: multiple CPU cores simultaneously execute multiple threads
More exciting content, the public may be concerned about my number
