11554 Want TCP_CONGESTION socket option
Reviewed by: Yuri Pankov <yuri.pankov@nexenta.com>

*** 148,157 ****
--- 148,165 ----
       cwnd to a specified number of TCP segments.  This applies to the cases
       when the connection first starts and restarts after an idle period.  The
       process must have the PRIV_SYS_NET_CONFIG privilege if it wants to
       specify a number greater than that calculated by RFC 3390.
  
+      The operating system also provides alternative algorithms that may be
+      more appropriate for your application, including the CUBIC congestion
+      control algorithm described in RFC 8312.  These can be configured system-
+      wide using ipadm(1M), or on a per-connection basis with the TCP-level
+      socket option TCP_CONGESTION, whose argument is the name of the algorithm
+      to use (for example "cubic").  If the requested algorithm does not exist,
+      then setsockopt() will fail, and errno will be set to ENOENT.
+ 
     TCP Keep-Alive
       Since TCP determines whether a remote peer is no longer reachable by
       timing out waiting for acknowledgements, a host that never sends any new
       data may never notice a peer that has gone away.  While consumers can
       avoid this problem by sending their own periodic heartbeat messages