Asynchronous Function Call in PHP

[Tuấn Dương Trần]

Hi every body, 
I'm building a website using Yii2, Redis, mysql. I need to write a function marking the songs, scores are stored in Redis and mysql. Scoring function using ajax to call the controler. I want this function to run in sequence as follows: The number is stored in Redis and returns immediately, then use a background thread to save the results into mysql. How i can do? 

Thanks.