Differences between processes and threads

process ：

         After the program saved on the hard disk runs , It will form an independent memory body in the memory space , This memory has its own address space , Has its own pile , The superior affiliated unit is the operating system . The operating system will be in process units , Allocate system resources （CPU Time slice 、 Memory and other resources ）, A process is the smallest unit of resource allocation .

Threads ：

           Threads are also called lightweight processes , It's operating system scheduling , yes CPU Minimum unit of scheduling .

         Thread is subordinate to process , It's the actual executor of the program . A process can have multiple threads , At least one thread , But a thread can only have one process .

coroutines ：

         coroutines , Also called tasklet , fibers ; It's a lighter existence than threads

           Thread switching will be saved to CPU In my stack , It has its own register context and stack

         The main function of a coroutine is to achieve concurrency under the condition of a single thread , But it's actually serial ( image yield equally )

         A coroutine can have , The process is not managed by the operating system kernel , And it's completely controlled by the program .