Dongyang's study notes
Processes and threads
- Each process has its own independent space. "In the same process" or "not in the same process" is an important decision point for the division of system functions.
- Threads are characterized by sharing address space, thereby efficiently sharing data. Multiple processes on a machine can efficiently share code segments (the operating system can be mapped to the same physical memory ), but cannot share data. If multiple processes share a large amount of memory, it is tantamount to writing a multi-process program as a multi-threaded program.
Why use multithreading
The author believes that it is to better play the performance of multi-core processors. If there is only one CPU and one execution unit, it is the most efficient to write the program according to the state machine idea.