Note that in the example when it says "Send file with approximately 20 kbyte/s." that is only an upper bound. The file could still be sent at a lesser speed (e.g. 10 kb/s) if the client, network, or server, cannot handle the amount.
(PECL pecl_http >= 0.10.0)
http_throttle — HTTP throttling
Sets the throttle delay and send buffer size.
Note: Provides a basic throttling mechanism, which will yield the current process or thread until the entity has been completely sent.
This may not work as expected with the following SAPI(s): FastCGI.
seconds to sleep after each chunk sent
the chunk size in bytes
Example #1 A http_throttle() example
Send file with approximately 20 kbyte/s.
// ~ 20 kbyte/s
# http_throttle(1, 20000);
# http_throttle(0.5, 10000);