ltm rule command TCP rtt

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



TCP::rtt
       Returns the smoothed round-trip time estimate for a TCP connection.

SYNOPSIS
       TCP::rtt

DESCRIPTION
       Returns the smoothed round-trip time estimate for a TCP connection.

       Syntax

       TCP::rtt

	    * Returns the smoothed round-trip time estimate for a TCP connection.

	      Note that the value returned is in units of "1/32 of a millisecond".
	      (Divide the returned value by 32 to get the actual round trip time in milliseconds.)
	      Note that the rtt takes some time to converge, so we recommend using ROUTE::rttvar
	      to get the statistical variance of rtt in 1/16 ms intervals & cull outliers.

RETURN VALUE
VALID DURING
       CLIENT_ACCEPTED, CLIENT_CLOSED, CLIENT_DATA, SERVER_CLOSED,
       SERVER_CONNECTED, SERVER_DATA, SIP_REQUEST, SIP_REQUEST_SEND,
       SIP_RESPONSE, STREAM_MATCHED

EXAMPLES
	when HTTP_RESPONSE {
	clientside { set rtt [TCP::rtt] }
	if {$rtt < 1600 } {
	      log "NOcompress rtt=$rtt"
	      COMPRESS::disable
	   }
	else {
	      log "compress rtt=$rtt"
	      COMPRESS::enable
	      COMPRESS::gzip level 9
	   }
	}

HINTS
SEE ALSO
CHANGE LOG
       @BIGIP-9.0.0 --First introduced the command.



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