Fix: ThreadPool max threads (#2035)

Author: BornToBeRoot

Source/NETworkManager.Localization/Resources/Strings.Designer.cs

@@ -3290,10 +3290,9 @@ If the option is disabled again, the values are no longer modified. However, the
     <value>ThreadPool additional min. threads</value>
   </data>
   <data name="HelpMessage_ThreadPoolAdditionalMinThreads" xml:space="preserve">
-    <value>This setting sets the minimum number of threads used by the application's ThreadPool. This can improve the performance of e.g. the IP scanner or port scanner.
-The value is added to the default settings.
-
-The value 0 leaves the default settings (number of CPU threads).
+    <value>This setting specifies the minimum number of threads that will be created from the application's ThreadPool on demand. This can improve the performance for example of the IP scanner or port scanner.
+	
+The value is added to the default min. threads (number of CPU threads). The value 0 leaves the default settings. If the value is higher than the default max. threads of the ThreadPool, this value is used.
 
 If the value is too high, performance problems may occur.
 

Source/NETworkManager.Localization/Resources/Strings.resx

@@ -163,6 +163,7 @@ by BornToBeRoot
 
         if (mutexIsAcquired || SettingsManager.Current.Window_MultipleInstances)
         {
+            // Setup background job
             if (SettingsManager.Current.General_BackgroundJobInterval != 0)
             {
                 _log.Info($"Setup background job with interval {SettingsManager.Current.General_BackgroundJobInterval} minute(s)...");
@@ -179,14 +180,23 @@ by BornToBeRoot
                 _log.Info("Background job is disabled.");
             }
 
-            // Modify the thread pool to increase performance for IP Scanner & Port Scanner
-            ThreadPool.GetMinThreads(out var workerThreads, out var completionPortThreads);            
-            var setMinThreadsResult = ThreadPool.SetMinThreads(workerThreads + SettingsManager.Current.General_ThreadPoolAdditionalMinThreads, completionPortThreads + SettingsManager.Current.General_ThreadPoolAdditionalMinThreads);
+            // Setup ThreadPool for the application
+            ThreadPool.GetMaxThreads(out var workerThreadsMax, out var completionPortThreadsMax);
+            ThreadPool.GetMinThreads(out var workerThreadsMin, out var completionPortThreadsMin);
 
-            if (setMinThreadsResult)
-                _log.Info($"ThreadPool min threads set to workerThreads: {workerThreads} + {SettingsManager.Current.General_ThreadPoolAdditionalMinThreads}, completionPortThreads: {completionPortThreads} + {SettingsManager.Current.General_ThreadPoolAdditionalMinThreads}.");
+            var workerThreadsMinNew = workerThreadsMin + SettingsManager.Current.General_ThreadPoolAdditionalMinThreads;
+            var completionPortThreadsMinNew = completionPortThreadsMin + SettingsManager.Current.General_ThreadPoolAdditionalMinThreads;
+
+            if (workerThreadsMinNew > workerThreadsMax)
+                workerThreadsMinNew = workerThreadsMax;
+
+            if (completionPortThreadsMinNew > completionPortThreadsMax)
+                completionPortThreadsMinNew = completionPortThreadsMax;
+                        
+            if (ThreadPool.SetMinThreads(workerThreadsMinNew, completionPortThreadsMinNew))
+                _log.Info($"ThreadPool min threads set to: workerThreads: {workerThreadsMinNew}, completionPortThreads: {completionPortThreadsMinNew}");
             else
-                _log.Warn($"ThreadPool min thread could not be set to workerThreads: {workerThreads} + {SettingsManager.Current.General_ThreadPoolAdditionalMinThreads}, completionPortThreads: {completionPortThreads} + {SettingsManager.Current.General_ThreadPoolAdditionalMinThreads}.");
+                _log.Warn($"ThreadPool min threads could not be set to workerThreads: {workerThreadsMinNew}, completionPortThreads: {completionPortThreadsMinNew}");
 
             // Show splash screen
             if (SettingsManager.Current.SplashScreen_Enabled)