Hierarchical system of modern computer storage

In a computer system, the storage level can be divided into three levels: cache, main memory and auxiliary memory. Cache is used to improve the speed matching between main memory and CPU. The auxiliary memory is used to expand the storage space.

The performance of storage system is becoming more and more important in computers. The main reasons are:

1, Von Neumann architecture is based on the concept of stored programs, and memory access operations account for about 70% of CPU time.

2. The quality of storage management and organization affects the efficiency of the whole machine.

3. Modern information processing, such as image processing, database, knowledge base, speech recognition, multimedia, etc. , the storage system is very demanding.

Internal storage (memory)

Internal storage is directly related to? CPU？ Connection consists of electronic components with faster access speed but smaller storage capacity. It is used to store the instructions and data of the currently running program and exchange information directly with the CPU, which is the main source of data processing by the CPU.

Memory consists of many memory cells, and each memory cell can store a binary number or an instruction represented by a binary code. The internal memory consists of random access memory and read-only memory. Read only memory (ROM) is used for machine startup initialization and system default device parameter setting.