Poll the nic on the sampler's cadence, and reboot rather than exit when a clean return reaches PID 1

counters.go

@@ -80,10 +80,10 @@ func sumFields(base string, fields []string) uint64 {
 
 // A poll is an ioctl and a handful of sysfs attributes, each costing
 // microseconds of open and read, so it runs here rather than on the goroutine
-// that has a frame to draw every sixteen milliseconds. Off that path the
-// interval can be short enough that an unplugged cable shows up as a link error
-// while the hand is still on it.
-const nicInterval = 200 * time.Millisecond
+// that has a frame to draw every sixteen milliseconds. Off that path it can
+// match the sampler's cadence, so a link error lands on the panel as quickly
+// as a lost frame rather than stepping five times a second.
+const nicInterval = sampleInterval
 
 type nicPoller struct {
 	txBase string

main.go

@@ -535,6 +535,14 @@ func main() {
 	if err := run(*aName, *bName, *nsPerM); err != nil {
 		panic(err)
 	}
+	// A clean return is ctrl-alt-delete, which the kernel hands PID 1 as a
+	// SIGINT. Exiting on it would panic the kernel over the reboot it was asking
+	// for, so init asks for the reboot by name.
+	if os.Getpid() == 1 {
+		if err := unix.Reboot(unix.LINUX_REBOOT_CMD_RESTART); err != nil {
+			panic(err)
+		}
+	}
 }
 
 const (