ltm rule command TCP rttvar

iRule(1)		      BIG-IP TMSH Manual		      iRule(1)



TCP::rttvar
       Returns TCP's smoothed RTT variance estimate.

SYNOPSIS
       TCP::rttvar

DESCRIPTION
       Returns the Round Trip Time Variance, which is an indication of path
       jitter. TCP uses this figure, combined with RTT, to compute the RTO.

       Note that the value returned is in units of "1/16 of a millisecond".
       Divide the returned value by 16 to get the actual variance in
       milliseconds.

RETURN VALUE
       The measured RTT variance in units of "1/16 of a millisecond". Divide
       the returned value by 16 to get the actual variance in milliseconds.

VALID DURING
       ANY_EVENT

EXAMPLES
	when CLIENT_CLOSED {
	    # Log rttvar.
	    log local0. "rttvar: [TCP::rttvar]"
	}

HINTS
SEE ALSO
CHANGE LOG
       @BIGIP-12.0.0 --First introduced the command.



BIG-IP				  2017-01-31			      iRule(1)