Code:
/ Dotnetfx_Vista_SP2 / Dotnetfx_Vista_SP2 / 8.0.50727.4016 / DEVDIV / depot / DevDiv / releases / Orcas / QFE / wpf / src / Shared / MS / Win32 / handlecollector.cs / 1 / handlecollector.cs
using System; using MS.Win32 ; using System.Runtime.InteropServices; namespace MS.Win32 { internal static class HandleCollector { private static HandleType[] handleTypes; private static int handleTypeCount = 0; private static Object handleMutex = new Object(); ////// Adds the given handle to the handle collector. This keeps the /// handle on a "hot list" of objects that may need to be garbage /// collected. /// internal static IntPtr Add(IntPtr handle, int type) { handleTypes[type - 1].Add(); return handle; } internal static SafeHandle Add(SafeHandle handle, int type) { handleTypes[type - 1].Add(); return handle; } ////// Registers a new type of handle with the handle collector. /// internal static int RegisterType(string typeName, int expense, int initialThreshold) { lock (handleMutex) { if (handleTypeCount == 0 || handleTypeCount == handleTypes.Length) { HandleType[] newTypes = new HandleType[handleTypeCount + 10]; if (handleTypes != null) { Array.Copy(handleTypes, 0, newTypes, 0, handleTypeCount); } handleTypes = newTypes; } handleTypes[handleTypeCount++] = new HandleType(typeName, expense, initialThreshold); return handleTypeCount; } } ////// Removes the given handle from the handle collector. Removing a /// handle removes it from our "hot list" of objects that should be /// frequently garbage collected. /// internal static IntPtr Remove(IntPtr handle, int type) { handleTypes[type - 1].Remove(); return handle ; } internal static SafeHandle Remove(SafeHandle handle, int type) { handleTypes[type - 1].Remove(); return handle ; } ////// Represents a specific type of handle. /// private class HandleType { internal readonly string name; private int initialThreshHold; private int threshHold; private int handleCount; private readonly int deltaPercent; ////// Creates a new handle type. /// internal HandleType(string name, int expense, int initialThreshHold) { this.name = name; this.initialThreshHold = initialThreshHold; this.threshHold = initialThreshHold; this.deltaPercent = 100 - expense; } ////// Adds a handle to this handle type for monitoring. /// internal void Add() { bool performCollect = false; lock(this) { handleCount++; performCollect = NeedCollection(); if (!performCollect) { return; } } if (performCollect) { #if DEBUG_HANDLECOLLECTOR Debug.WriteLine("HC> Forcing garbage collect"); Debug.WriteLine("HC> name :" + name); Debug.WriteLine("HC> threshHold :" + (threshHold).ToString()); Debug.WriteLine("HC> handleCount :" + (handleCount).ToString()); Debug.WriteLine("HC> deltaPercent:" + (deltaPercent).ToString()); #endif GC.Collect(); // We just performed a GC. If the main thread is in a tight // loop there is a this will cause us to increase handles forever and prevent handle collector // from doing its job. Yield the thread here. This won't totally cause // a finalization pass but it will effectively elevate the priority // of the finalizer thread just for an instant. But how long should // we sleep? We base it on how expensive the handles are because the // more expensive the handle, the more critical that it be reclaimed. int sleep = (100 - deltaPercent) / 4; System.Threading.Thread.Sleep(sleep); } } ////// Determines if this handle type needs a garbage collection pass. /// internal bool NeedCollection() { if (handleCount > threshHold) { threshHold = handleCount + ((handleCount * deltaPercent) / 100); #if DEBUG_HANDLECOLLECTOR Debug.WriteLine("HC> NeedCollection: increase threshHold to " + threshHold); #endif return true; } // If handle count < threshHold, we don't // need to collect, but if it 10% below the next lowest threshhold we // will bump down a rung. We need to choose a percentage here or else // we will oscillate. // int oldThreshHold = (100 * threshHold) / (100 + deltaPercent); if (oldThreshHold >= initialThreshHold && handleCount < (int)(oldThreshHold * .9F)) { #if DEBUG_HANDLECOLLECTOR Debug.WriteLine("HC> NeedCollection: throttle threshhold " + threshHold + " down to " + oldThreshHold); #endif threshHold = oldThreshHold; } return false; } ////// Removes the given handle from our monitor list. /// internal void Remove() { lock(this) { handleCount--; handleCount = Math.Max(0, handleCount); } } } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved. using System; using MS.Win32 ; using System.Runtime.InteropServices; namespace MS.Win32 { internal static class HandleCollector { private static HandleType[] handleTypes; private static int handleTypeCount = 0; private static Object handleMutex = new Object(); ////// Adds the given handle to the handle collector. This keeps the /// handle on a "hot list" of objects that may need to be garbage /// collected. /// internal static IntPtr Add(IntPtr handle, int type) { handleTypes[type - 1].Add(); return handle; } internal static SafeHandle Add(SafeHandle handle, int type) { handleTypes[type - 1].Add(); return handle; } ////// Registers a new type of handle with the handle collector. /// internal static int RegisterType(string typeName, int expense, int initialThreshold) { lock (handleMutex) { if (handleTypeCount == 0 || handleTypeCount == handleTypes.Length) { HandleType[] newTypes = new HandleType[handleTypeCount + 10]; if (handleTypes != null) { Array.Copy(handleTypes, 0, newTypes, 0, handleTypeCount); } handleTypes = newTypes; } handleTypes[handleTypeCount++] = new HandleType(typeName, expense, initialThreshold); return handleTypeCount; } } ////// Removes the given handle from the handle collector. Removing a /// handle removes it from our "hot list" of objects that should be /// frequently garbage collected. /// internal static IntPtr Remove(IntPtr handle, int type) { handleTypes[type - 1].Remove(); return handle ; } internal static SafeHandle Remove(SafeHandle handle, int type) { handleTypes[type - 1].Remove(); return handle ; } ////// Represents a specific type of handle. /// private class HandleType { internal readonly string name; private int initialThreshHold; private int threshHold; private int handleCount; private readonly int deltaPercent; ////// Creates a new handle type. /// internal HandleType(string name, int expense, int initialThreshHold) { this.name = name; this.initialThreshHold = initialThreshHold; this.threshHold = initialThreshHold; this.deltaPercent = 100 - expense; } ////// Adds a handle to this handle type for monitoring. /// internal void Add() { bool performCollect = false; lock(this) { handleCount++; performCollect = NeedCollection(); if (!performCollect) { return; } } if (performCollect) { #if DEBUG_HANDLECOLLECTOR Debug.WriteLine("HC> Forcing garbage collect"); Debug.WriteLine("HC> name :" + name); Debug.WriteLine("HC> threshHold :" + (threshHold).ToString()); Debug.WriteLine("HC> handleCount :" + (handleCount).ToString()); Debug.WriteLine("HC> deltaPercent:" + (deltaPercent).ToString()); #endif GC.Collect(); // We just performed a GC. If the main thread is in a tight // loop there is a this will cause us to increase handles forever and prevent handle collector // from doing its job. Yield the thread here. This won't totally cause // a finalization pass but it will effectively elevate the priority // of the finalizer thread just for an instant. But how long should // we sleep? We base it on how expensive the handles are because the // more expensive the handle, the more critical that it be reclaimed. int sleep = (100 - deltaPercent) / 4; System.Threading.Thread.Sleep(sleep); } } ////// Determines if this handle type needs a garbage collection pass. /// internal bool NeedCollection() { if (handleCount > threshHold) { threshHold = handleCount + ((handleCount * deltaPercent) / 100); #if DEBUG_HANDLECOLLECTOR Debug.WriteLine("HC> NeedCollection: increase threshHold to " + threshHold); #endif return true; } // If handle count < threshHold, we don't // need to collect, but if it 10% below the next lowest threshhold we // will bump down a rung. We need to choose a percentage here or else // we will oscillate. // int oldThreshHold = (100 * threshHold) / (100 + deltaPercent); if (oldThreshHold >= initialThreshHold && handleCount < (int)(oldThreshHold * .9F)) { #if DEBUG_HANDLECOLLECTOR Debug.WriteLine("HC> NeedCollection: throttle threshhold " + threshHold + " down to " + oldThreshHold); #endif threshHold = oldThreshHold; } return false; } ////// Removes the given handle from our monitor list. /// internal void Remove() { lock(this) { handleCount--; handleCount = Math.Max(0, handleCount); } } } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved.
Link Menu
![Network programming in C#, Network Programming in VB.NET, Network Programming in .NET](/images/book.jpg)
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- CollectionTraceRecord.cs
- ValidatingReaderNodeData.cs
- SizeChangedEventArgs.cs
- ButtonFieldBase.cs
- CachedTypeface.cs
- Listbox.cs
- MemberProjectionIndex.cs
- XmlFormatExtensionPrefixAttribute.cs
- ConfigPathUtility.cs
- GridViewRow.cs
- ToolStripPanelRenderEventArgs.cs
- SqlDataSourceFilteringEventArgs.cs
- BindingCompleteEventArgs.cs
- ThreadStaticAttribute.cs
- EntityDataSourceReferenceGroup.cs
- SvcFileManager.cs
- UriParserTemplates.cs
- DataControlImageButton.cs
- DtdParser.cs
- OrderedDictionary.cs
- ItemsControlAutomationPeer.cs
- SizeAnimation.cs
- DirectoryNotFoundException.cs
- SchemaType.cs
- GradientStop.cs
- IIS7UserPrincipal.cs
- InvokeProviderWrapper.cs
- QueueSurrogate.cs
- LogicalCallContext.cs
- BaseValidatorDesigner.cs
- MappedMetaModel.cs
- GenericPrincipal.cs
- DataGridViewRowConverter.cs
- AxHostDesigner.cs
- ComponentTray.cs
- FlowLayoutSettings.cs
- BatchWriter.cs
- RichTextBoxConstants.cs
- AssociatedControlConverter.cs
- InProcStateClientManager.cs
- dtdvalidator.cs
- WebDisplayNameAttribute.cs
- WebBrowserNavigatedEventHandler.cs
- HtmlInputControl.cs
- TextEncodedRawTextWriter.cs
- RoleManagerSection.cs
- TimeSpanStorage.cs
- TableAutomationPeer.cs
- DataGridTableCollection.cs
- AgileSafeNativeMemoryHandle.cs
- CompilerWrapper.cs
- PolygonHotSpot.cs
- CacheMode.cs
- Blend.cs
- PrintDialog.cs
- DSASignatureFormatter.cs
- Hash.cs
- DrawingCollection.cs
- ResourceProviderFactory.cs
- DataSourceIDConverter.cs
- Trustee.cs
- HealthMonitoringSection.cs
- SystemFonts.cs
- BorderGapMaskConverter.cs
- UTF8Encoding.cs
- DropShadowEffect.cs
- IntSecurity.cs
- FixedSOMPageElement.cs
- CheckedPointers.cs
- Mutex.cs
- OracleDataReader.cs
- XmlRawWriter.cs
- PageBuildProvider.cs
- InProcStateClientManager.cs
- WebPartManagerInternals.cs
- TrackingQuery.cs
- IgnoreDataMemberAttribute.cs
- MulticastOption.cs
- TableCell.cs
- WebBrowserHelper.cs
- GradientStop.cs
- MenuRendererStandards.cs
- PersistNameAttribute.cs
- DocumentPageViewAutomationPeer.cs
- ISCIIEncoding.cs
- ShaderEffect.cs
- CodeCastExpression.cs
- BitmapSource.cs
- ReachPrintTicketSerializer.cs
- URLString.cs
- HttpResponseHeader.cs
- CompilationUnit.cs
- FilteredAttributeCollection.cs
- WorkflowTerminatedException.cs
- ControlBuilderAttribute.cs
- FormViewCommandEventArgs.cs
- TranslateTransform.cs
- WebSysDisplayNameAttribute.cs
- EventManager.cs
- DataObjectSettingDataEventArgs.cs