Windows NT calls system services by using an "int 2e" software interrupt. The "int 2e" instruction uses both an interrupt gate and a code segment descriptor to find the interrupt service routine (KiSystemService) which services the "int 2e" software interrupt. Since the CPU will have to load one interrupt gate and one segment descriptor from memory in order to know what interrupt service routine to call, significant overhead is involved in making an "int 2e" system call. The SYSENTER instruction drastically reduces this overhead.
Latest System Articles - Page 9
How Do Windows NT System Calls REALLY Work?
Learn about the exact mechanism that Windows NT uses when switching to kernel mode to execute a system service. The description is for an x86-compatible CPU running in protected mode. Other platforms supported by Windows NT will have a similar mechanism for switching to kernel mode.
The K.I.S.S. Approach to I/O Completion Ports
I/O completion ports are the holy grail of performance. This article provides an extremely lightweight and open framework for easily implementing IOCP's in your application(s).
Windows Thread Pooling
Thread pooling describes a technique by which threads of execution are managed and to which work is distributed. Additional semantics such as concurrency control may also be defined. Thread pooling is a nice way to: Manage complexity Make your applications scale Introduce new code while minimizing risk
Java/C++ PC Standby Detect and Prevent
Shows how to detect whether the computer is going to go into sleep (standby) mode and allow/disallow it.
Creating an MMC Snapin Using C# (Part I)
Learn how to create an MMC Snapin using C#.
Latest Developer Videos
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MFC Integration with the Windows Transactional File System (TxF)
The Transactional File System (TxF), which allows access to an NTFS file system to be conducted in a transacted manner through extensions to the Windows SDK API. MFC 10, has been extended to support TxF and related technologies. This support allows existing MFC applications to be easily extended to support kernel transactions.
.NET Framework: Collections and Generics
The original release of the .NET Framework included collections as .NET was introduced to the Microsoft programming world. The .NET Framework 2.0 introduced generics to complement the System.Collections namespace and provide a more efficient and well performing option. Read on to learn more...

Disabling Titlebar Buttons with VB.NET
Hannes du Preez shows you how to disable titlebar buttons and menus in your programs temporarily.

WebSockets Meets Security
WebSockets are intended to build bi-directional connections between a web browser and a server. This must be done in a safe way. In addition, the WebSockets have a huge disadvantage (to say it politely). Read on to learn more.
