Calculate and display load average.

code/espurna/config/general.h

@@ -168,6 +168,12 @@
 #define HEARTBEAT_REPORT_VERSION    1
 #define HEARTBEAT_REPORT_INTERVAL   0
 
+//------------------------------------------------------------------------------
+// Load average
+//------------------------------------------------------------------------------
+#define LOADAVG_INTERVAL        30000   // Interval between calculating load average (in ms)
+#define LOADAVG_REPORT          1       // Should we report Load average over MQTT?
+
 //------------------------------------------------------------------------------
 // RESET
 //------------------------------------------------------------------------------
@@ -595,6 +601,7 @@ PROGMEM const char* const custom_reset_string[] = {
 #define MQTT_TOPIC_RFRAW        "rfraw"
 #define MQTT_TOPIC_UARTIN       "uartin"
 #define MQTT_TOPIC_UARTOUT      "uartout"
+#define MQTT_TOPIC_LOADAVG      "loadavg"
 
 // Light module
 #define MQTT_TOPIC_CHANNEL      "channel"

code/espurna/system.ino

@@ -26,6 +26,9 @@ bool _system_send_heartbeat = false;
 
 bool _systemStable = true;
 
+// Calculated load average 0 to 100;
+unsigned short int _load_average = 100;
+
 void systemCheck(bool stable) {
     unsigned char value = EEPROM.read(EEPROM_CRASH_COUNTER);
     if (stable) {
@@ -72,14 +75,31 @@ void systemLoop() {
 
     #if HEARTBEAT_ENABLED
         // Heartbeat
-        static unsigned long last = 0;
-        if (_system_send_heartbeat || (last == 0) || (millis() - last > HEARTBEAT_INTERVAL)) {
+        static unsigned long last_hbeat = 0;
+        if (_system_send_heartbeat || (last_hbeat == 0) || (millis() - last_hbeat > HEARTBEAT_INTERVAL)) {
             _system_send_heartbeat = false;
-            last = millis();
+            last_hbeat = millis();
             heartbeat();
         }
     #endif // HEARTBEAT_ENABLED
 
+    // Increase temporary loop counter
+    static unsigned long load_counter_temp = 0;
+    static unsigned long load_counter = 0;
+    static unsigned long load_counter_max = 1;
+    static unsigned long last_loadcheck = 0;
+
+    load_counter_temp++;
+    if (millis() - last_loadcheck > LOADAVG_INTERVAL) {
+      load_counter = load_counter_temp;
+      load_counter_temp = 0;
+      if (load_counter > load_counter_max) {
+        load_counter_max = load_counter;
+      }
+      _load_average = 100 - (100 * load_counter / load_counter_max);
+      last_loadcheck = millis();
+    }
+
     // Power saving delay
     delay(_loopDelay);
 
@@ -120,3 +140,7 @@ void systemSetup() {
     espurnaRegisterLoop(systemLoop);
 
 }
+
+unsigned long getLoadAverage() {
+  return _load_average;
+}

code/espurna/utils.ino

@@ -172,6 +172,9 @@ void heartbeat() {
             #if (HEARTBEAT_REPORT_STATUS)
                 mqttSend(MQTT_TOPIC_STATUS, MQTT_STATUS_ONLINE, true);
             #endif
+            #if (LOADAVG_REPORT)
+                mqttSend(MQTT_TOPIC_LOADAVG, String(getLoadAverage()).c_str());
+            #endif
         }
     #endif
 

code/espurna/ws.ino

@@ -220,6 +220,7 @@ void _wsUpdate(JsonObject& root) {
     root["heap"] = getFreeHeap();
     root["uptime"] = getUptime();
     root["rssi"] = WiFi.RSSI();
+    root["loadaverage"] = getLoadAverage();
     #if NTP_SUPPORT
         if (ntpSynced()) root["now"] = now();
     #endif

code/html/index.html

@@ -223,6 +223,9 @@
                                     <div class="pure-u-1-2 pure-u-lg-1-4">Uptime</div>
                                     <div class="pure-u-11-24 pure-u-lg-17-24"><span class="right" name="uptime"></span></div>
 
+                                    <div class="pure-u-1-2 pure-u-lg-1-4">Load average</div>
+                                    <div class="pure-u-11-24 pure-u-lg-17-24"><span class="right" name="loadaverage"></span>%</div>
+
                                     <div class="pure-u-1-2 pure-u-lg-1-4">Free heap</div>
                                     <div class="pure-u-11-24 pure-u-lg-17-24"><span class="right" name="heap" post=" bytes"></span></div>