diff --git a/cddl/lib/libdtrace/siftr.d b/cddl/lib/libdtrace/siftr.d
--- a/cddl/lib/libdtrace/siftr.d
+++ b/cddl/lib/libdtrace/siftr.d
@@ -54,12 +54,12 @@
 	uint32_t		snd_ssthresh;
 	int			conn_state;
 	u_int			max_seg_size;
-	int			smoothed_rtt;
+	uint32_t		srtt;
 	u_char			sack_enabled;
 	u_char			snd_scale;
 	u_char			rcv_scale;
 	u_int			flags;
-	int			rxt_length;
+	uint32_t		rto;
 	u_int			snd_buf_hiwater;
 	u_int			snd_buf_cc;
 	u_int			rcv_buf_hiwater;
@@ -84,12 +84,12 @@
 	snd_ssthresh =		p == NULL ? 0 : p->snd_ssthresh;
 	conn_state =		p == NULL ? 0 : p->conn_state;
 	max_seg_size = 		p == NULL ? 0 : p->max_seg_size;
-	smoothed_rtt =		p == NULL ? 0 : p->smoothed_rtt;
+	srtt =			p == NULL ? 0 : p->srtt;
 	sack_enabled = 		p == NULL ? 0 : p->sack_enabled;
 	snd_scale =		p == NULL ? 0 : p->snd_scale;
 	rcv_scale =		p == NULL ? 0 : p->rcv_scale;
 	flags =			p == NULL ? 0 : p->flags;
-	rxt_length = 		p == NULL ? 0 : p->rxt_length;
+	rto =			p == NULL ? 0 : p->rto;
 	snd_buf_hiwater =	p == NULL ? 0 : p->snd_buf_hiwater;
 	snd_buf_cc = 		p == NULL ? 0 : p->snd_buf_cc;
 	rcv_buf_hiwater = 	p == NULL ? 0 : p->rcv_buf_hiwater;
diff --git a/share/man/man4/dtrace_tcp.4 b/share/man/man4/dtrace_tcp.4
--- a/share/man/man4/dtrace_tcp.4
+++ b/share/man/man4/dtrace_tcp.4
@@ -346,12 +346,8 @@
 .Pa /usr/lib/dtrace/tcp.d .
 .It Vt u_int max_seg_size
 The maximum segment size for the flow, in bytes.
-.It Vt int smoothed_rtt
-The current smoothed RTT estimate for the flow, in units of TCP_RTT_SCALE * HZ,
-where TCP_RTT_SCALE is a define found in
-.Pa /usr/include/netinet/tcp_var.h ,
-and HZ is the kernel's tick timer.
-Divide by TCP_RTT_SCALE * HZ to get the RTT in secs.
+.It Vt uint32_t srtt
+The current smoothed RTT (SRTT) for the flow in microseconds.
 .It Vt u_char sack_enabled
 SACK enabled indicator. 1 if SACK enabled, 0 otherwise.
 .It Vt u_char snd_scale
@@ -360,9 +356,8 @@
 The current window scaling factor for the receiving window.
 .It Vt u_int flags
 The current value of the t_flags for the flow.
-.It Vt int rxt_length
-The current retransmission timeout length for the flow, in units of HZ, where HZ
-is the kernel's tick timer.
+.It Vt uint32_t rto
+The current retransmission timeout (RTO) for the flow in microseconds.
 Divide by HZ to get the timeout length in seconds.
 .It Vt u_int snd_buf_hiwater
 The current size of the socket send buffer in bytes.