laravel queues - how sync driver works? Does it executes in a seperated process or the main execution thread?

After some research, I've decided to go with database driver. There are some other great options as well, but the choice will depend on your system workload.

The point is, sync driver uses the main thread for execution of tasks which is useful for only when you are in development. If you have a production system then you might need to consider some other option to run your queue. The main idea of queuing long-running tasks is to be able to execute them in some background process so your main application thread won't block and you can serve your client requests more quickly.

For further information on different drivers and help please visit Laravel docs