Create request object only after the first byte was received. Previously, we always created an object and logged 400 (Bad Request) in access log if a client closed connection without sending any data. Such a connection was counted as "reading". Since it's common for modern browsers to behave like this, it's no longer considered an error if a client closes connection without sending any data, and such a connection will be counted as "waiting". Now, we do not log 400 (Bad Request) and keep memory footprint as small as possible.