Improve documentation,for
@@ -142,11 +142,13 @@ These options control the behaviour of **carbon-c-relay**.
connection refused errors on the clients.
* `-U` *bufsize*:
- Sets the socket send/receive buffer sizes in bytes. When unset, the
- OS default is used. The maximum is also determined by the OS. The
- sizes are set using setsockopt with the flags SO_RCVBUF and
- SO_SNDBUF. Setting this size may be necessary for large volume
- scenarios, for which also `-B` might apply.
+ Sets the socket send/receive buffer sizes in bytes, for both TCP and UDP
+ scenarios. When unset, the OS default is used. The maximum is also
+ determined by the OS. The sizes are set using setsockopt with the flags
+ SO_RCVBUF and SO_SNDBUF. Setting this size may be necessary for large
+ volume scenarios, for which also `-B` might apply. Checking the *Recv-Q*
+ and the *receive errors* values from *netstat* gives a good hint
+ about buffer usage.
* `-T` *timeout*:
Specifies the IO timeout in milliseconds used for server connections.
