Detailed introduction of distributed pressure measurement system VIII: basic introduction of akka actor model

actor Model

Previous picture , I got it online ：

It looks like sending email , Think of this model as sending email , And there's a mailbox , It seems to be multi person communication , One actor It's just one person ,actor Communicate with each other , Using email . I have used email at ordinary times , What are the characteristics of email , Is the advantage of asynchronous non blocking , The sender may not care when the receiver receives , Whether it has been handled , He just sends it to his mailbox , Of course, the recipient is also , He doesn't care who sent it to him , If he wants to deal with the mail, he takes it out of the mailbox , Process according to the specific email content .

characteristic

1. Asynchronous non-blocking , Those who write letters belong to those who write letters , Write it and put it in the mailbox , The receiver belongs to the receiver , Deal with it whenever you want , In fact, it is similar to message queue , Send a message to the queue and it's done , Go on with the rest , That is, the thread can not wait .
2. Data is isolated from each other , Event driven , Those who write letters cannot control the receipt , What the recipient wants to do is up to him , His own data can only be modified by himself , Relative to others is isolation , That is, there is no need to share data , Maintain their own data , Only modify the data according to the incoming letter , And the letters are orderly in the queue , The time to deal with it is 1 Sealed , Therefore, there is no concurrent data sharing problem
3. No need for synchronous lock , There is no shared data , There is no need for synchronous lock
4. Good concurrency , There is no need for threads to synchronize in order to share resources , Greatly improve the utilization of threads

akka System structure

Whole actor In fact, it is an attribute structure , It should be convenient for unified management, scheduling and query ：

akka Core elements

akka Dependencies between core elements

You can see ,actorCell You can visit Actor, however actorCell It's internal ,Actor No direct access , therefore ,Actor You can't directly modify another Actor The state of , Thread safety can be achieved

akka actor System initialization process

akka actor The system creates a node process

akka actor Send and process messages

The above are sorted out from the source code , There may be something wrong , Some specific details should be read by yourself .
Okay , That's it today , I hope it is helpful for learning and understanding , Don't spray when the great God sees , Only for their own learning and understanding , Limited ability , Please forgive me .