Nginx Download speed limit

You should include a directive as this in your nginx configuration file (inside the block of yourserver configuration):

 limit_rate  150k  ;    

This limits the speed of transmission of the answer to the client. It works as a limit for each connection, not for the total server transfer rate. (Maybe you can adjust max_clients =worker_processes*worker_connectionsAs a work-around to limit total transfer.)

Take a look at the Nginx documentation for Limit_rate. There is also a directive the is useful to set the this limit only after limit_rate_after download exceeds certain size.

Nginx Download speed limit