Hello Alexl,
That is the configured limit for HTTP and HTTPS connections to your server. In your case, if you ever have 80,000 HTTP/HTTPS connections or 40,000 HTTPS connections in use at the same time, the next connection of that type will have to wait until an existing connection closes and is freed up for use.
(80,000 limit is applied to any type of connection, 40,000 limit is only applied to HTTPS)
Both of these limits are configurable.
Regards,
-Michael