zeus-server/bandwidth-throttler (packagist): This library can be used to limit (throttle) the speed of files served for download. It intercepts the PHP script output by setting a buffering handler that is called every time a given number of bytes are served to the browser. The library measures the time since the last time the PHP output buffer was flushed and hold on PHP for a while if the average download speed is above a given limit.
Keywords: throttle|bandwidth|download speed|download limit|transfer limit|transfer speed|buffer|burst|download|limit|performance|php|qos|speed|throttling|transfer