Modify the ConfigLoader.cc file

config.example.json

@@ -47,8 +47,9 @@
     }
   ],*/
   "app": {
-    //threads_num:num of threads,1 by default
-    "threads_num": 16,
+    //threads_num:the number of IO threads,1 by default, if the value is set to 0, the number of threads
+    //will be the number of processors.
+    "threads_num": 1,
     //enable_session:false by default
     "enable_session": false,
     "session_timeout": 0,
@@ -132,4 +133,4 @@
     //of the connection without read or write
     "idle_connection_timeout": 60
   }
-}
+}

lib/src/ConfigLoader.cc

@@ -19,6 +19,8 @@
 #include <iostream>
 #include <fstream>
 #include <unistd.h>
+#include <thread>
+
 using namespace drogon;
 
 ConfigLoader::ConfigLoader(const std::string &configFile)
@@ -136,6 +138,14 @@ static void loadApp(const Json::Value &app)
         return;
     //threads number
     auto threadsNum = app.get("threads_num", 1).asUInt64();
+    if (threadsNum == 0)
+    {
+        //set the number to the number of processors.
+        threadsNum = std::thread::hardware_concurrency();
+        LOG_DEBUG << "The number of processors is " << threadsNum;
+    }
+    if (threadsNum < 1)
+        threadsNum = 1;
     drogon::app().setThreadNum(threadsNum);
     //session
     auto enableSession = app.get("enable_session", false).asBool();