Added heap used and total heap statistics.

README.md

@@ -23,7 +23,9 @@ Here is the list of data the module reports periodically:
        utcstart: <when the process was started>,
        events: <number of new reports being processed since last stats reporting>,,
        cpu: <cpu usage>,
-       mem: <memory usage>,
+       mem: <ratio of used to total heap memory used>,
+       usedheap: <v8 heap memory used>,
+       totalheap: <v8 total heap size>,
        cpuperreq: <cpu usage per request>,
        oreqs: <current open requests count>,
        sys_cpu: <system cpu load>,

src/monitor.cc

@@ -53,7 +53,7 @@ static bool _show_backtrace = false;  //< default to false for performance
 // However, if there is no receiver on the other end (i.e. sendmsg()
 // returns -1), then the reporting thread will wait MAX_INACTIVITY_RETRIES
 // before trying again.
-static const int REPORT_INTERVAL_MS = 1000;
+static const int REPORT_INTERVAL_MS = 5000;
 static const int MAX_INACTIVITY_RETRIES = 5;
 
 /* globals used for signal catching, etc */
@@ -404,6 +404,8 @@ void NodeMonitor::setStatistics() {
         Nan::GetHeapStatistics(&v8stats);
 
         stats_.pmem_ = (v8stats.used_heap_size() / (double) v8stats.total_heap_size());
+        stats_.usedheap_ = v8stats.used_heap_size();
+        stats_.totalheap_ = v8stats.total_heap_size();
     }
 
     {   // Obtains the CPU usage
@@ -786,6 +788,12 @@ bool NodeMonitor::sendReport() {
         data.append(buffer);
     }
 
+    snprintf(buffer, sizeof(buffer), "\"usedheap\":%d,", stats.usedheap_);
+    data.append(buffer);
+
+    snprintf(buffer, sizeof(buffer), "\"totalheap\":%d,", stats.totalheap_);
+    data.append(buffer);
+
     // requests served since beginning 
     snprintf(buffer, sizeof(buffer), "\"reqstotal\":%d,", stats.lastRequests_);
     data.append(buffer);

src/monitor.h

@@ -224,6 +224,10 @@ typedef struct {
     volatile time_t healthStatusTimestamp_;
 
     volatile double pmem_;
+
+    volatile int usedheap_;
+
+    volatile int totalheap_;
 } Statistics;