diff --git a/sonoff/_releasenotes.ino b/sonoff/_releasenotes.ino
index 17df37b0c..1c8956f59 100644
--- a/sonoff/_releasenotes.ino
+++ b/sonoff/_releasenotes.ino
@@ -1,4 +1,5 @@
 /* 6.0.0a
+ * Add heap and stack debug information
  * Add command SetOption28 to switch between hex or decimal Sonoff Bridge RF received data format (#3008)
  * Add command SetOption29 to switch between hex or decimal IR received data format
  * Add performance improvement when updating multiple individual WS2812 pixels (#3007)
diff --git a/sonoff/sonoff.h b/sonoff/sonoff.h
index 5d641f5fb..3ad6ee096 100644
--- a/sonoff/sonoff.h
+++ b/sonoff/sonoff.h
@@ -194,7 +194,7 @@ enum LichtSubtypes {LST_NONE, LST_SINGLE, LST_COLDWARM, LST_RGB, LST_RGBW, LST_R
 enum LichtSchemes {LS_POWER, LS_WAKEUP, LS_CYCLEUP, LS_CYCLEDN, LS_RANDOM, LS_MAX};
 
 enum XsnsFunctions {FUNC_PRE_INIT, FUNC_INIT, FUNC_LOOP, FUNC_EVERY_50_MSECOND, FUNC_EVERY_SECOND, FUNC_PREP_BEFORE_TELEPERIOD, FUNC_JSON_APPEND, FUNC_WEB_APPEND, FUNC_SAVE_BEFORE_RESTART,
-                    FUNC_COMMAND, FUNC_MQTT_SUBSCRIBE, FUNC_MQTT_INIT, FUNC_MQTT_DATA, FUNC_SET_POWER, FUNC_SHOW_SENSOR, FUNC_RULES_PROCESS};
+                    FUNC_COMMAND, FUNC_MQTT_SUBSCRIBE, FUNC_MQTT_INIT, FUNC_MQTT_DATA, FUNC_SET_POWER, FUNC_SHOW_SENSOR, FUNC_RULES_PROCESS, FUNC_FREE_MEM};
 
 const uint8_t kDefaultRfCode[9] PROGMEM = { 0x21, 0x16, 0x01, 0x0E, 0x03, 0x48, 0x2E, 0x1A, 0x00 };
 
diff --git a/sonoff/sonoff.ino b/sonoff/sonoff.ino
index 0f56d1492..fec987722 100644
--- a/sonoff/sonoff.ino
+++ b/sonoff/sonoff.ino
@@ -391,6 +391,8 @@ void MqttDataHandler(char* topic, byte* data, unsigned int data_len)
   uint16_t index;
   uint32_t address;
 
+  ShowFreeMem(PSTR("MqttDataHandler"));
+
   strncpy(topicBuf, topic, sizeof(topicBuf));
   for (i = 0; i < data_len; i++) {
     if (!isspace(data[i])) break;
@@ -1266,6 +1268,7 @@ void ExecuteCommand(char *cmnd, int source)
   char *start;
   char *token;
 
+  ShowFreeMem(PSTR("ExecuteCommand"));
   ShowSource(source);
 
   token = strtok(cmnd, " ");
diff --git a/sonoff/xdrv_01_mqtt.ino b/sonoff/xdrv_01_mqtt.ino
index a860e6717..77c1e88f4 100644
--- a/sonoff/xdrv_01_mqtt.ino
+++ b/sonoff/xdrv_01_mqtt.ino
@@ -204,6 +204,8 @@ void MqttPublishDirect(const char* topic, boolean retained)
   char sretained[CMDSZ];
   char slog_type[10];
 
+  ShowFreeMem(PSTR("MqttPublishDirect"));
+
   sretained[0] = '\0';
   snprintf_P(slog_type, sizeof(slog_type), PSTR(D_LOG_RESULT));
 
diff --git a/sonoff/xdrv_10_rules.ino b/sonoff/xdrv_10_rules.ino
index ed849011d..38b62cf95 100644
--- a/sonoff/xdrv_10_rules.ino
+++ b/sonoff/xdrv_10_rules.ino
@@ -343,6 +343,8 @@ bool RulesProcessEvent(char *json_event)
 {
   bool serviced = false;
 
+  ShowFreeMem(PSTR("RulesProcessEvent"));
+
   String event_saved = json_event;
   event_saved.toUpperCase();
 
diff --git a/sonoff/xdrv_99_debug.ino b/sonoff/xdrv_99_debug.ino
index eecb59e3a..5aa1f4231 100644
--- a/sonoff/xdrv_99_debug.ino
+++ b/sonoff/xdrv_99_debug.ino
@@ -165,11 +165,11 @@ void CpuLoadLoop()
 #if defined(F_CPU) && (F_CPU == 160000000L)
       int CPU_load = 100 - ( (CPU_loops*(1 + 30*sleep)) / (CPU_load_check *800) );
       CPU_loops = CPU_loops / CPU_load_check;
-      snprintf_P(log_data, sizeof(log_data), PSTR(D_LOG_APPLICATION "FreeRam %d, CPU %d%%(160MHz), Loops/sec %d"), ESP.getFreeHeap(), CPU_load, CPU_loops);
+      snprintf_P(log_data, sizeof(log_data), PSTR(D_LOG_DEBUG "FreeRam %d, CPU %d%%(160MHz), Loops/sec %d"), ESP.getFreeHeap(), CPU_load, CPU_loops);
 #else
       int CPU_load = 100 - ( (CPU_loops*(1 + 30*sleep)) / (CPU_load_check *400) );
       CPU_loops = CPU_loops / CPU_load_check;
-      snprintf_P(log_data, sizeof(log_data), PSTR(D_LOG_APPLICATION "FreeRam %d, CPU %d%%(80MHz), Loops/sec %d"), ESP.getFreeHeap(), CPU_load, CPU_loops);
+      snprintf_P(log_data, sizeof(log_data), PSTR(D_LOG_DEBUG "FreeRam %d, CPU %d%%(80MHz), Loops/sec %d"), ESP.getFreeHeap(), CPU_load, CPU_loops);
 #endif
       AddLog(LOG_LEVEL_DEBUG);
       CPU_last_millis = CPU_last_loop_time;
@@ -180,6 +180,26 @@ void CpuLoadLoop()
 
 /*******************************************************************************************/
 
+extern "C" {
+#include <cont.h>
+  extern cont_t g_cont;
+}
+
+void DebugFreeMem()
+{
+//  https://github.com/esp8266/Arduino/issues/2557
+  register uint32_t *sp asm("a1");
+
+//  snprintf_P(log_data, sizeof(log_data), PSTR(D_LOG_DEBUG "FreeRam %d, FreeStack %d, UnmodifiedStack %d (%s)"),
+//    ESP.getFreeHeap(), 4 * (sp - g_cont.stack), cont_get_free_stack(&g_cont), XdrvMailbox.data);
+
+  snprintf_P(log_data, sizeof(log_data), PSTR(D_LOG_DEBUG "FreeRam %d, FreeStack %d (%s)"),
+    ESP.getFreeHeap(), 4 * (sp - g_cont.stack), XdrvMailbox.data);
+  AddLog(LOG_LEVEL_DEBUG);
+}
+
+/*******************************************************************************************/
+
 void DebugCfgDump(char* parms)
 {
   #define CFG_COLS 16
@@ -347,6 +367,9 @@ boolean Xdrv99(byte function)
     case FUNC_COMMAND:
       result = DebugCommand();
       break;
+    case FUNC_FREE_MEM:
+      DebugFreeMem();
+      break;
   }
   return result;
 }
diff --git a/sonoff/xdrv_interface.ino b/sonoff/xdrv_interface.ino
index 6080b103b..16bac5830 100644
--- a/sonoff/xdrv_interface.ino
+++ b/sonoff/xdrv_interface.ino
@@ -176,6 +176,14 @@ boolean XdrvRulesProcess()
   return XdrvCall(FUNC_RULES_PROCESS);
 }
 
+void ShowFreeMem(const char *where)
+{
+  char stemp[20];
+  snprintf_P(stemp, sizeof(stemp), where);
+  XdrvMailbox.data = stemp;
+  XdrvCall(FUNC_FREE_MEM);
+}
+
 /*********************************************************************************************\
  * Function call to all xdrv
  *
@@ -191,6 +199,7 @@ boolean XdrvRulesProcess()
  * FUNC_EVERY_SECOND
  * FUNC_EVERY_50_MSECOND
  * FUNC_RULES_PROCESS
+ * FUNC_FREE_MEM
 \*********************************************************************************************/
 
 boolean XdrvCall(byte Function)