add checks for non-empty CPU times during initialization (#401)

agent/cpu.go

@@ -14,10 +14,10 @@ var lastPerCoreCpuTimes = make(map[uint16][]cpu.TimesStat)
 // init initializes the CPU monitoring by storing the initial CPU times
 // for the default 60-second cache interval.
 func init() {
-	if times, err := cpu.Times(false); err == nil {
+	if times, err := cpu.Times(false); err == nil && len(times) > 0 {
 		lastCpuTimes[60000] = times[0]
 	}
-	if perCoreTimes, err := cpu.Times(true); err == nil {
+	if perCoreTimes, err := cpu.Times(true); err == nil && len(perCoreTimes) > 0 {
 		lastPerCoreCpuTimes[60000] = perCoreTimes
 	}
 }

supplemental/scripts/install-agent.sh

@@ -871,6 +871,8 @@ EOF
 
 elif is_freebsd; then
   echo "Checking for existing FreeBSD service configuration..."
+  # Ensure rc.d directory exists on minimal FreeBSD installs
+  mkdir -p /usr/local/etc/rc.d
   
   # Create environment configuration file with proper permissions if it doesn't exist
   if [ ! -f "$AGENT_DIR/env" ]; then