Optimize RegistryCache

Author: sergiye

winMemoryOptimizer/Engine/ComputerService.cs

@@ -20,6 +20,7 @@ internal class ComputerService {
     public static bool HasSystemWorkingSet => OperatingSystemHelper.IsWindowsXpOrGreater;
     public static bool HasModifiedFileCache => OperatingSystemHelper.IsWindowsXpOrGreater;
     public static bool HasSystemFileCache => OperatingSystemHelper.IsWindowsXpOrGreater;
+    public static bool HasRegistryCache => OperatingSystemHelper.IsWindows81OrGreater;
 
     private WindowsStructs.MemoryStatusEx memoryStatusEx;
 
@@ -234,6 +235,27 @@ public void Optimize(Enums.MemoryAreas areas, Enums.OptimizationReason reason) {
         }
       }
 
+      if ((areas & Enums.MemoryAreas.RegistryCache) != 0) {
+        try {
+          if (OnOptimizeProgressUpdate != null) {
+            value++;
+            OnOptimizeProgressUpdate(value, "Registry Cache");
+          }
+
+          stopwatch.Restart();
+
+          OptimizeRegistryCache();
+
+          runtime = runtime.Add(stopwatch.Elapsed);
+
+          infoLog.AppendLine(string.Format(infoLogFormat, "Registry Cache", "Optimized",
+            stopwatch.Elapsed.TotalSeconds, "seconds"));
+        }
+        catch (Exception e) {
+          errorLog.AppendLine(string.Format(errorLogFormat, "Registry Cache", "Error", e.GetMessage()));
+        }
+      }
+
       if (infoLog.Length > 0) {
         infoLog.Insert(0,
           $"{"Memory areas".ToUpper()} ({runtime.TotalSeconds:0.0} seconds){Environment.NewLine}{Environment.NewLine}");
@@ -508,6 +530,14 @@ private static void OptimizeSystemFileCache() {
         throw new Win32Exception(Marshal.GetLastWin32Error());
     }
 
+    private void OptimizeRegistryCache() {
+      if (!HasRegistryCache)
+        throw new Exception("The Registry Cache optimization is not supported on this version of the operating system");
+
+      if (NativeMethods.NtSetSystemInformation(Constants.Windows.SystemInformationClass.SystemRegistryReconciliationInformation, IntPtr.Zero, 0) != Constants.Windows.SystemErrorCode.ErrorSuccess)
+        throw new Win32Exception(Marshal.GetLastWin32Error());
+    }
+
     private static SafeFileHandle OpenVolumeHandle(string driveLetter) {
       if (string.IsNullOrWhiteSpace(driveLetter))
         return null;

winMemoryOptimizer/Engine/Constants.cs

@@ -24,6 +24,7 @@ public static class SystemInformationClass {
         public const int SystemCombinePhysicalMemoryInformation = 130; // 0x82
         public const int SystemFileCacheInformation = 21; // 0x15
         public const int SystemMemoryListInformation = 80; // 0x50
+        public const int SystemRegistryReconciliationInformation = 155; // 0x9B
       }
 
       public static class SystemMemoryListCommand {

winMemoryOptimizer/Engine/Enums.cs

@@ -23,6 +23,7 @@ public enum MemoryAreas {
       SystemWorkingSet = 32,
       ModifiedFileCache = 64,
       SystemFileCache = 128,
+      RegistryCache = 256,
     }
 
     public enum MemoryUnit {

winMemoryOptimizer/TrayApplicationContext.cs

@@ -218,6 +218,8 @@ private static Enums.MemoryAreas GetEnabledMemoryAreas() {
         Settings.MemoryAreas &= ~Enums.MemoryAreas.ModifiedFileCache;
       if (!ComputerService.HasSystemFileCache)
         Settings.MemoryAreas &= ~Enums.MemoryAreas.SystemFileCache;
+      if (!ComputerService.HasRegistryCache)
+        Settings.MemoryAreas &= ~Enums.MemoryAreas.RegistryCache;
       return Settings.MemoryAreas;
     }
 
@@ -238,6 +240,8 @@ private static int GetEnabledMemoryAreasCount() {
         result++;
       if (Settings.MemoryAreas.HasFlag(Enums.MemoryAreas.SystemFileCache))
         result++;
+      if (Settings.MemoryAreas.HasFlag(Enums.MemoryAreas.RegistryCache))
+        result++;
       return result;
     }
 
@@ -522,6 +526,9 @@ private void AddMenuItems() {
         optimizationTypesMenu.DropDownItems.Add(new ToolStripMenuItem("System File Cache", null, (_, _) => {
           ToggleMemoryArea(Enums.MemoryAreas.SystemFileCache);
         }) { Tag = Enums.MemoryAreas.SystemFileCache });
+        optimizationTypesMenu.DropDownItems.Add(new ToolStripMenuItem("Registry Cache", null, (_, _) => {
+          ToggleMemoryArea(Enums.MemoryAreas.RegistryCache);
+        }) { Tag = Enums.MemoryAreas.RegistryCache });
       }
       optimizationTypesMenu.DropDown.Closing += OnContextMenuStripClosing;
       UpdateAreasMenuItems();