fix: improve the calculation of available memory in the docker

lib/orders/system.js

@@ -375,12 +375,27 @@ var getLoadAvg = function (callback) {
 
 var dockerFreeMemory = function (callback) {
   const mem_used_path = path.join(cgroupBaseDir, '/memory/memory.usage_in_bytes');
-  fs.readFile(mem_used_path, 'utf8', function (err, data) {
+  const mem_stat_path = path.join(cgroupBaseDir, '/memory/memory.stat');
+
+  fs.readFile(mem_used_path, 'utf8', function (err, mem_used) {
     if (err) {
       return callback(err);
     }
-    var used = Number(data.trim());
-    return callback(null, totalMemory - used);
+
+    const used_size = Number(mem_used.trim());
+    fs.readFile(mem_stat_path, 'utf8', function (err, mem_stat) {
+      if (err) {
+        return callback(err);
+      }
+
+      const mem_stat_obj = mem_stat.trim().split('\n').map(v => v.split(' '))
+        .reduce((r, v) => { r[v[0]] = v[1]; return r; }, {});
+      const total_active_file_size = Number(mem_stat_obj.total_active_file.trim());
+      const total_inactive_file_size = Number(mem_stat_obj.total_inactive_file.trim());
+
+      const freeMemory = totalMemory - used_size + (total_active_file_size + total_inactive_file_size);
+      return callback(null, freeMemory);
+    });
   });
 };
 
@@ -406,7 +421,7 @@ var linuxFreeMemroy = function (callback) {
 
       if (isMemAvailable) {
         if (pair[0] === 'MemAvailable') {
-          free =  parseInt(pair[1], 10) * 1024;
+          free = parseInt(pair[1], 10) * 1024;
         }
       } else {
         if (['MemFree', 'Buffers', 'Cached'].indexOf(pair[0]) >= 0) {
@@ -448,7 +463,7 @@ var getFreeMemory = function (callback) {
   }
 };
 
-var initTotalMemory = function() {
+var initTotalMemory = function () {
   totalMemory = os.totalmem();
   if (!isDocker) {
     // keep os.totalmem()

package.json

@@ -37,4 +37,4 @@
     "client.js",
     "start_client.js"
   ]
-}
+}