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Native Image Generator | Reference | OpenTuwa | OpenTuwa — Solo Journalism

From Wikipedia, the free encyclopedia

Native Image Generator

Service of the .NET framework

The Native Image Generator, or simply NGen, is the ahead-of-time compilation (AOT) service of the .NET Framework. It allows a CLI assembly to be pre-compiled instead of letting the Common Language Runtime (CLR) do a just-in-time compilation (JIT) at runtime. In some cases the exe

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The Native Image Generator, or simply NGen, is the ahead-of-time compilation (AOT) service of the .NET Framework.^[1] It allows a CLI assembly to be pre-compiled instead of letting the Common Language Runtime (CLR) do a just-in-time compilation (JIT) at runtime. In some cases the execution will be significantly faster than with JIT.

General information

The Native Image Generator produces a native binary image for the current environment (i.e.; operating systems). This eliminates the JIT overhead at the expense of portability and disk space; whenever an NGen-generated image is run in an incompatible environment, .NET Framework automatically reverts to using JIT. Once NGen is run against an assembly, the resulting native image is placed into the Native Image Cache (NIC) for use by all other CLI assemblies. This makes it possible, for example, to use NGen to process CLI assemblies at installation time, saving processor time later on, when the end-user invokes the application on their system.

NGen is intended to make the assembly execute faster by removing the JIT compilation process at runtime, but this does not always improve performance because some optimizations can be done only by a JIT compiler (e.g., if the JIT compiler knows that the code is already running with full trust, it can skip certain expensive security checks). Because of this fact, it makes sense to use NGen only after benchmarking the application performance before and after it.

References

↑ Vermeir, Nico (2022). "Runtimes and Desktop Packs". Introducing .NET 6. Berkeley, California: Apress. doi:10.1007/978-1-4842-7319-7_2.

External links

Wikibooks has a book on the topic of: .NET Development Foundation

.NET

Implementations

Architecture

Components

ADO.NET
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- WCF Data Services
Windows Forms (WinForms)
Windows Identity Foundation (WIF)
Windows Presentation Foundation (WPF)
Windows Workflow Foundation (WF)
.NET Remoting

Tools

Decompilers	.NET Reflector dotPeek
Obfuscators	Dotfuscator SmartAssembly
CLR Profiler ILAsm .NET Compiler Platform Native Image Generator (NGen) XAMLPad

IDEs

Organizations

Microsoft development tools

Development
environments

Visual Studio	Code Express Team System Profiler Tools for Applications Tools for Office
Others	Blend Expression Web FxCop GW-BASIC MACRO-80 Macro Assembler MSBuild Pascal QuickBASIC QBasic QuickC Robotics Developer Studio Roslyn SharePoint Designer FrontPage Small Basic WebMatrix Windows App SDK Windows App Studio Windows SDK CLR Profiler ILAsm Native Image Generator WinDiff XAMLPad

Languages

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BASIC
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APIs and
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Native	Windows API Silverlight XNA DirectX Managed DirectX UWP Xbox Development Kit Windows Installer WinUI
.NET	ASP.NET Core AJAX Dynamic Data MVC Razor Web Forms ADO.NET Entity Framework MAUI CardSpace Communication Foundation Identity Foundation LINQ Presentation Foundation Workflow Foundation
Device drivers	WDK WDF KMDF UMDF Windows HLK WDM

Database

SQL Server	Express Compact Management Studio MSDE
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