Fairy LoRe

SYMPTOMS

Computers that are equipped with multiple processors that support processor power management features, such as Advanced Configuration and Power Interface (ACPI) processor performance states, require Microsoft Windows XP Service Pack 2 (SP2). Additional updates are available to optimize performance and behavior on computers that are running Windows XP SP2. Without these updates, computers that are equipped with these power management-capable, mobile, dual-core processors may experience decreased performance or unexpected behavior.

This problem also applies to x64-based versions of Microsoft Windows Server 2003.

RESOLUTION

The following file is available for download from the Microsoft Download Center: Download the WindowsXP-KB896256-v4-x86-ENU.exe package now

You must restart the computer after you apply this update.

MORE INFORMATION

loadTOCNode(1, ‘moreinformation’);Windows XP SP2 is required on computers that have multiple CPUs that support ACPI processor performance states. This requirement includes computers that support the following items:

• Multiple physical sockets
• Multiple-core designs
• Multiple logical threads, such as Intel hyper-threading technology

Because Windows XP was not originally designed to support performance states on multiprocessor configurations, changes are required to correctly realize this support on multiprocessor systems. Windows XP Service Pack 2 includes the required changes to the kernel power manager. These changes make sure that Windows XP correctly functions on multiprocessor systems with processor performance states.

This hotfix also addresses the following issues on computers that have multiple processors that support processor performance states:

• A possible decrease in performance on single-threaded workloads when processor performance states are using demand-based switching.
• The synchronization of the processor Time Stamp Counter (TSC) registers across processors when you use the ACPI Power Management timer on multiprocessor systems.
• ACPI C-state promotion and demotion issues in the kernel power manager.

Update details

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Possible decrease in performance during demand-based switching

loadTOCNode(3, ‘moreinformation’);Demand-Based Switching (DBS) is the use of ACPI processor performance states (dynamic voltage and frequency scaling) in response to system workloads. Windows XP processor power management implements DBS by using the adaptive processor throttling policy. This policy dynamically and automatically adjusts the processor’s current performance state in response to system CPU use without user intervention.

When single-threaded workloads run on multiprocessor systems that include dual-core configurations, the workloads may migrate across available CPU cores. This behavior is a natural artifact of how Windows schedules work across available CPU resources. However, on systems that have processor performance states that run with the adaptive processor throttling policy, this thread migration may cause the Windows kernel power manager to incorrectly calculate the optimal target performance state for the processor. This behavior occurs because an individual processor core, logical or physical, may appear to be less busy than the whole processor package actually is. On performance benchmarks that use single-threaded workloads, you may see this artifact in decreased performance results or in a high degree of variance between successive runs of identical benchmark tests.

This hotfix includes changes to the kernel power manager to track CPU use across the processor package. These changes enable visibility into the true activity level of a CPU complex and therefore help correctly calculate an increased target performance state.

This solution favors performance gains over power savings. Although benchmark performance scores may improve, battery life could be negatively affected. Accordingly, this kernel policy change may be disabled by a registry key to allow for maximum flexibility.

How to disable the new performance state policy behavior

loadTOCNode(3, ‘moreinformation’);Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

After you install the hotfix that is described in this article, you may use registry settings to disable the new performance state policy behavior. To do this, follow these steps:

1. Click Start, click Run, type regedit, and then click OK.
2. Right-click HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager, point to New, and then click Key.
3. Type Throttle for the new key name.
4. Right-click Throttle, point to New, and then click DWORD Value.
5. Type PerfEnablePackageIdle for the value name.
6. Right-click PerfEnablePackageIdle, and then click Modify.
7. In the Value data box, type 0. Make sure that Hexadecimal is selected in the Edit DWORD Value dialog box, and then click OK.
   • You can type 1 in the Value data box to enable the new performance state policy behavior.
8. Quit Registry Editor.

Correct TSC synchronization

loadTOCNode(3, ‘moreinformation’);On some operating systems, the processor TSC may change the rate at which it counts. Additionally, the processor TSC may stop counting when specific processor power management features are used. On computers that have multiple processors, the TSC is typically the operating system hardware timer that supports calls to the kernel KeQueryPerformanceCounter function. When TSC does not increment monotonically, system components that use the kernel KeQueryPerformanceCounter function may not work correctly. To address this problem, Microsoft makes it possible for the ACPI Power Management Timer to be used as the operating system timer that supports the kernel KeQueryPerformanceCounter function. However, some programs may directly access the TSC by bypassing the Windows timer APIs. The multiple-processor Hardware Abstraction Layer (HAL) makes sure that the TSC registers on all processors on a multiple-processor computer remain closely synchronized. Therefore, access by system software that may be directed to different processors does not return different results. This change makes sure that the multiple-processor HAL continues to correctly synchronize the TSCs across all processors on a computer, even if the ACPI power management timer is used as the operating system hardware timer.

Ja, es ist einer dieser Tests, über den viele schon einmal nachgedacht, aber niemals selber ausprobiert haben. Auf welchem Computer läuft Windows XP noch? Microsoft gibt selbst bescheidene 233 MHz und 64 MB Arbeitsspeicher an, doch es geht noch viel weiter nach unten.

So wurde in einem schicken Versuchsaufbau nach und nach getestet, wie weit man die Taktschraube nach unten drehen kann. Angefangen wurde bei 100 MHz und 64 MB Speicher, welches man dann Test für Test immer weiter heruntertrieb. Endergebnis waren erstaunliche 8 MHz bei einem Arbeitsspeicher von 20 MB mit einer ISA-Grafikkarte. Windows XP benötigt dabei allein zum Starten runde 30 Minuten. Doch das ist noch nicht alles. Bei besagten Frequenzen ist sogar Internet drin, wenn man so gute zehn Minuten Zeit pro Seite mitbringt.

Weitere Informationen, der ausführliche Versuchsaufbau und Benchmarks gibt es auf der Homepage von Winhistory.

Here are th names of the useful MMC Console tools (.msc) that come with Windows XP. You can run them directly by typing their name in the Start / Run… or by pressing the Start button + R (german keyboards U):

compmgmt.msc – Computer management
devmgmt.msc – Device manager
diskmgmt.msc – Disk management
dfrg.msc – Disk defrag
eventvwr.msc – Event viewer
fsmgmt.msc – Shared folders
gpedit.msc – Group policies
lusrmgr.msc – Local users and groups
perfmon.msc – Performance monitor
rsop.msc – Resultant set of policies
secpol.msc – Local security settings
services.msc – Services

What is ClearType?
ClearType is a software technology developed by Microsoft that improves the readability of text on existing LCDs (Liquid Crystal Displays), such as laptop screens, Pocket PC screens and flat panel monitors. With ClearType font technology, the words on your computer screen look almost as sharp and clear as those printed on a piece of paper.

How to enable ClearType
- Right click on the Desktop and choose Properties
- Go to the Appearance Tab and click on the Effects button
- Put a tick in the “Use the following method to smooth edges of screen fonts” checkbox
- In the dropdown menu select “ClearType”

Although ClearType works pretty fine on CRT monitors, it is designed for LCD screens and gives the best results on such. I don’t advice you to use t on on CRT monitors, but you are welcome to try it

Find out more about ClearType …

Entgegen einer weitverbreiteten Auffassung ist Windows nicht das einzige Betriebssystem, in das Microsoft investiert. Mitarbeiter von Microsoft Research arbeiten an einem Mikrokernel, das von Windows völlig verschieden ist. Die Software liegt jetzt als Prototyp vor, sie heißt ‘Singularity‘.

Der Prototyp umfasst 300.000 Codezeilen. “Singularity ist nicht Windows. Wir haben jede Zeile ganz von vorn geschrieben”, sagte Galen Hunt, Microsoft Senior Researcher. Vor zwei Jahren habe ein Team mit der Arbeit an Singularity begonnen, mittlerweile seien damit 35 Forscher beschäftigt.

Microsoft Research habe das Ziel, “ein von Grund auf zuverlässiges Betriebssystem zu konstruieren”. Zudem lieferten die Forscher anderen Abteilungen Ideen – so dem Architectural Team der ‘Core Operating System Division’ (COSD) und dem Microsoft Security Team.

Singularity sei ein Resultat der Kombination aus Microsoft C# und Sing#, einem Derivat von C#. Weiteres Ziel sei, das ganze Betriebsystem mit Sing# zu schreiben, sagte Hunt. Singularity sei ohne Einsatz der Microsoft Common Language Runtime (CLR) und der Java Virtual Machine (JVM) entstanden. Das Team habe stattdessen ‘Bartok’ verwendet, eine selbst programmierte Entwicklerumgebung.

Ob Microsoft die Forschungsergebnisse kommerziell umsetzen wird, ist derweil ungewiss. Redmond könnte Singularity als eigenständiges Produkt auf den Markt bringen oder Komponenten der Software in andere Programme einbetten. Singularity könnte zudem als Host Operating System für Microsoft BigTop dienen, ein internes Infrastrukturprojekt des Herstellers.