Operating system, computer operating system
The teacher often said that it is easier to understand the problem from the perspective of asking questions, in this operating system study, I tried to simply understand the basic function management of the operating system in this way.
[Overall perception] operating systems are used in various fields. For us, we know the most about Windows systems installed on computers and Android systems on mobile phones. The operating components of computers are relatively scattered, it is easy for us to compare and learn.
Throughout the history of computer system development, it is constantly updated along with the development of hardware. From the initial batch processing system that can only be executed by a single job to a time-sharing operating system that can be executed by multiple programs together, to the subsequent real-time operating system that can collect information for intelligent processing; different application fields can be divided into: personal computer operating systems, network operating systems used by multiple people, and distributed operating systems. They are used in Embedded Operating Systems for intelligent industrial production.
You have long known about the computer structure: the host, controller, memory, input and output devices. The function of an operating system is to coordinate the structures of these computers and rationally allocate system resources so that they can serve people more quickly and efficiently. [Processor] The core component of a computer is the number of cpus. It contains controllers and processors. How does it work for computers?
The answer is through processing programs and data. In this way, the process came into being. The last execution of a program on a dataset is called a process. Why can't we visualize it as the basic unit of cpu execution. The execution of a process is often not a single linear processing process. It supports many parallel operations, so there is a thread, and the execution efficiency of the process is greatly improved. Concurrent operations of processes also increase job execution speed, but the application of data sharing becomes difficult, just as the front-end and the customer allocate a room, if only one room is left, and two people rent a house at the same time, two waiters may rent a house to two people, which is unreasonable. At this time, PV operations and process communication have played a huge role.
All kinds of errors and execution priorities will inevitably occur in the execution of any program. In this case, the interruption technology will have to be applied. Interrupt Processing is a transfer station and a scheduling processing method. When an error occurs or a process is converted, the existing program can be protected to convert the execution process to another program. [Storage] storage is a data storage factory. Due to different manufacturing processes, the access speeds of various storage devices vary. For cost considerations, different applications use different storage devices, so the storage speed is small and the price is not too high. The speed of access is from fast to slow: in order to make the memory run efficiently, it is managed by addressing. With the increasing capacity and restrictions on address lines and data lines, address compilation cannot simply adopt the number method. Page-based and segmented storage management improves the addressing efficiency. [File] the data storage problem is solved, and file management is an efficient data calling method. It implements name-based requests and Directory management. [Device] the real execution of jobs is done by devices. However, when multiple jobs need to use the same device at the same time, confusion will inevitably occur, in this case, the allocation of devices becomes the key to the efficient execution of jobs. The buffer technology completely solves the inconsistency between the logical record and the physical record that actually stores data.
[Summary] the operating system is an intelligent factory, which automatically completes a program that is prone to problems in many user operations. Through its learning, we have to have a higher respect for the wisdom of mankind.
