1, Clock period ：
Also known as oscillation period , It's the most basic part of the computer , Minimum time unit . In one clock cycle ,CPU Complete only one basic action .
2, Machine cycle ：
In the computer , In order to facilitate management , Dividing the execution process of an instruction into several stages , Complete a task at each stage . for example , Fetch command , Memory reading , Memory writing, etc , Each job is called a basic operation . Complete one
The time required for basic operation is called machine cycle .
3, Instruction cycle ：
The time required to execute an instruction , Generally, it consists of several machine cycles . usually , Instructions with one machine cycle are called single cycle instructions , Instructions with two machine cycles are called two cycle instructions .
4, Common performance metrics
MIPS： Average execution speed of single word long fixed-point instruction , Million machine language instructions processed per second . It's a measure CPU An indicator of speed .
MFLOPS： Millions of floating point operations per second , Measure the technical index of computer system , Can't reflect the overall situation , It can only reflect floating-point operation .
function ： Store programs and data , And high speed in the process of computer operation , To access programs or data automatically .
6, Memory mapping
Is a mapping from a file to a block of memory
. Memory mapped files are similar to virtual memory , An area of address space can be reserved by memory mapping file , Also commit physical storage to this area , The physical storage for memory file mapping comes from a file that already exists on disk , And you must map the file before you can operate on it . When using memory mapped files to process files stored on disk , Will no longer have to execute on files I/O operation , Make the memory mapping file
It can play an important role in processing large data files .
7, Data path ：
In digital system , Each subsystem passes the data bus
The data transmission path formed by connection is called data path . The design of data path directly affects the design of controller , It also affects the speed index and cost of the digital system . generally speaking , Fast digital system , There are many independent channels for information transmission .