Optimizing Windows XP for XenDesktop - · Consulting first addressed this topic in a white paper...

CONSULTING WHITE PAPER | Citrix XenDesktop

Optimizing Windows XP for XenDesktop

www.citrix.com

Citrix® XenDesktop™ 4.0


Contents

Introduction ........................................................................................................................................................ 1

Machine Settings ................................................................................................................................................ 1

Implementing Machine-based Registry Configurations .......................................................................... 1

Recommended Configurations .................................................................................................................... 2

Standard Mode Recommended Configurations........................................................................................ 3

Optional Configurations .............................................................................................................................. 3

Software Agent Configurations ................................................................................................................... 4

User Settings ....................................................................................................................................................... 4

Implementing User-based Registry Configurations ................................................................................. 4

User Profile Best Practices ........................................................................................................................... 5

Recommended Configurations .................................................................................................................... 6

Optional Configurations .............................................................................................................................. 7

Conclusion .......................................................................................................................................................... 9


1

Introduction

Citrix XenDesktop is a desktop virtualization solution that delivers a complete Windows desktop

experience as an on-demand service to any user, anywhere. Most large implementations of

XenDesktop thus far have been based on Microsoft Windows XP, although that is expected to

change quickly as Microsoft Windows 7 goes mainstream in the enterprise. Many early adopters of

XenDesktop have faced the challenging task of tuning Windows XP for a hosted VM-based VDI

desktop model. Typically, Windows operating systems are tuned based on whether they are a client

or server operating system. In the case of a hosted VM-based VDI desktop though, Windows XP is

a client operating system operating in more of a traditional server role in the datacenter.

Understanding this duality is just the beginning of optimizing Windows XP for XenDesktop.

While most server-based computing administrators have experience tuning server-based operating

systems like Windows Server 2003 to support hundreds of users, not as much knowledge is available

for tuning a client operating system like Windows XP for running in the datacenter. Citrix

Consulting first addressed this topic in a white paper entitled Best Practices for Citrix XenDesktop with

Provisioning Server which was released for XenDesktop 2.1. This document builds on that white paper

by providing a comprehensive view on optimizing Windows XP for a hosted VM-based VDI

desktop environment offering proven optimizations, providing specific registry values, and

explaining how to implement these configurations in ways that are supported by both Citrix and

Microsoft. These configurations typically add value by enhancing the user experience and increasing

system performance. For example, some of the changes optimize the user experience by enabling

faster logons, reducing unnecessary prompts, and quicker screen updates. Others optimize

performance and increase scalability by reducing unnecessary processor, memory, disk and network

usage.

Machine Settings

Machine settings are easier to implement than user settings as they are typically set once as part of

the base image. However, machine settings are more dependent on the exact deployment scenario,

particularly whether or not Windows XP is deployed on standard mode vDisk images with Citrix

Provisioning Services. Fortunately, many machine-level optimizations for standard mode vDisk

images are already included in the XenConvert Optimizer tool, which is installed as part of the

Provisioning Services target device software. The registry changes included with this tool are

indicated as such below. The software agents frequently installed on each desktop are also covered

in this section. However, strategies for deploying end-user applications to virtual desktops, such as

installing applications locally or streaming applications, are not covered in this document.

Implementing Machine-based Registry Configurations

Most of the configurations recommended in this document are changes to the registry. Registry

changes can be implemented in a number of ways and there is not necessarily one way that is best

for all deployments. Machine-based registry modifications can be set anytime during the base

image preparation or maintenance cycles. The simplest way to implement them is to modify the

http://support.citrix.com/article/ctx119849

http://support.citrix.com/article/ctx119849


2

registry manually using “regedit.exe” or creating and executing a “.REG” file. Automated ways

of modifying the registry, including Group Policy or other third-party tools, are also possible. All

registry modifications listed in this document use the “.REG” file syntax so that they can be

easily copied and pasted into a customized “.REG” file.

Caution: All of the registry settings mentioned in this document must be analyzed for benefit and risk to your

environment. Modifying the registry incorrectly can cause serious problems that may require you to reinstall the

operating system. Citrix cannot guarantee that problems resulting from incorrectly modifying the registry can be

solved. Modify the registry at your own risk. Backup the registry or disk image before making changes.

Recommended Configurations

The following registry changes are recommended for all deployment scenarios and would almost

always be desirable in a Windows XP hosted VM-based VDI desktop implementation:

Configuration Optimizer Registry Modification (in REG file format)

Disable Last Access

Timestamp

Yes [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\FileSystem]

"NtfsDisableLastAccessUpdate"=dword:00000001

Disable Indexing

Service

Yes [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\cisvc]

"Start"=dword:00000004

Disable Wireless

Zero Config. Service

No [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WZCSVC]


Disable Security

Center Service

No [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\wscsvc]


Disable Large Send

Offload

No [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\BNNS\Parameters]

"EnableOffload"=dword:00000000

Disable TCP/IP

Offload

No [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters]

"DisableTaskOffload"=dword:00000001

Increase Service

Startup Timeout

No [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control]

"ServicesPipeTimeout"=dword:0002bf20

Disable Windows

Tour

No [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Applets\Tour]

"RunCount"=dword:00000000

Hide Hard Error

Messages

No [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Windows]

"ErrorMode"=dword:00000002

Disable CIFS Change

Notifications

No [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer]

"NoRemoteRecursiveEvents"=dword:00000001

Disable Logon

Screensaver

No [HKEY_USERS\.DEFAULT\Control Panel\Desktop]

"ScreenSaveActive"="0"

Note: The Optimizer column indicates whether this registry change is included in the XenConvert Optimizer tool

that is installed with the Provisioning Services target device software.


3

Standard Mode Recommended Configurations

The next set of registry changes are recommended for images deployed using standard mode

vDisk images with Citrix Provisioning services. Standard mode images are unique in that they are

restored to the original state at each reboot, deleting any newly written or modified data. In this

scenario, certain processes are no longer efficient. These configurations may also apply when

deploying persistent images and in many cases should be implemented in addition to the changes

recommended in the preceding section.


Disable Offline

Files

Yes [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\NetCache]

"Enabled"=dword:00000000

Disable

Background

Defragmentation

Yes [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Dfrg\BootOptimizeFunction]

"Enable"="N"

Disable

Background

Layout Service

Yes [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\OptimalLayout]

"EnableAutoLayout"=dword:00000000

Disable System

Restore

Yes [Software\Policies\Microsoft\Windows NT\SystemRestore]

"DisableSR"=dword:00000001

Disable

Hibernation

Yes [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Power]

"Heuristics"=hex:05,00,00,00,00,01,00,00,00,00,00,00,00,00,00,00,3f,42,0f,00

Disable Memory

Dumps

Yes [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\CrashControl]

"CrashDumpEnabled"=dword:00000000

"LogEvent"=dword:00000000

"SendAlert"=dword:00000000

Disable Move to

Recycle Bin

Yes [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\BitBucket]

"UseGlobalSettings"=dword:00000001

"NukeOnDelete"=dword:00000001

Disable Mach.

Acct. Password

Changes

Yes [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netlogon\Parameters]

"DisablePasswordChange"=dword:00000001

Disable Windows

Update Service

Yes [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\wuauserv]


Optional Configurations

This last set of machine-based registry changes is optional regardless of whether the image is

deployed as a persistent or standard image. In many cases, the following configurations should

be implemented; however, these configurations should be analyzed for suitability to each unique

environment.


Disable Themes

Service

No [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Themes]



4

Software Agent Configurations

While the previous subsections have covered optimizations to Windows XP itself, it is also

important to consider the impact of third party agents and other helper applications installed on

Windows XP, many of which run automatically. It is critical to minimize the impact of software

agents wherever possible. An agent consuming a small amount of resources can easily consume

an entire CPU core or gigabytes of memory when the physical server hosts 100+ virtualized

Windows XP desktops. In addition, all of the background processing could negatively affect

user experience, which is critical to the success of a desktop virtualization solution. While this

document does not go into this topic in detail, the following are a few common optimizations to

review.

Remove Unneeded Programs from the Run Key. After installing all third party

applications into the image, it is important to analyze the user and machine “Startup”

paths and “Run” keys (typically, HKLM\Software\Microsoft\Windows\Current

Version\Run). Many common applications, such as Adobe Reader and Java, add helper

applications to these locations so that the software can check for updates and load more

quickly. However, these helper applications are typically undesirable in a hosted VM-

based VDI desktop deployment as they consume resources and can prompt users

unnecessarily. Each application should be tested to ensure that preventing the helper

application from launching automatically does not break the application.

Optimize Antivirus Scanning. It is important to review the antivirus software

configuration. Citrix recommends scanning on write events to local drives only in order

to minimize processing time. It is also recommended to exclude the paging file and print

spool folder. When deploying standard mode vDisk images, Citrix recommends regularly

updating the antivirus signatures in the base image.

EdgeSight Configuration. Citrix recommends additional antivirus configurations when

using EdgeSight. See Citrix Knowledge Center article CTX111062 for more information.

User Settings

Unlike machine settings, user settings must be applied to each user and typically cannot be applied as

part of the base image. In addition, user settings typically do not depend on whether the image is

deployed in private or standard mode; however, the method in which the settings should be applied

can be influenced by the image mode. None of the configurations in this section are included in the

XenConvert Optimizer tool. These factors make user settings more difficult to implement.

Implementing User-based Registry Configurations

Many optimization recommendations suggest overwriting the default user profile of the base

image to implement user-specific settings. When overwriting the default user profile, each new

user receives a copy of the modified default user profile as their initial user profile. This method

has the benefit of being relatively easy to implement. However, this approach has significant

http://support.citrix.com/article/CTX111062


5

drawbacks in that it is known to cause several issues, particularly with Windows 7, as well as

being explicitly unsupported by Microsoft. (See http://blogs.technet.com/deploymentguys/

archive/2009/10/29/configuring-default-user-settings-full-update-for-windows-7-and-windows-

server-2008-r2.aspx.) In addition, this approach does not affect users that already have a roaming

profile.

A preferred alternative is to configure each user’s profile “on demand” as the user logs in. These

settings can be implemented using Microsoft Group Policy Preferences or a login script. To

ensure an optimal user experience, this must be implemented in conjunction with persistent user

profiles using a solution such as Citrix Profile Management, Windows roaming profiles, or

another third party solution. With this method, the initial logon may take several additional

seconds for Windows to build the user profile for the first time. After the initial logon, the logon

time will be noticeably reduced for all subsequent logons. Some user settings may not take effect

until the user logs in for the second time. This solution provides very fast logon times to users

while allowing administrators to implement almost any change on the fly without the hassle of

rebuilding profiles.

There are some additional considerations to be aware of, though. First, Windows XP roaming

profiles can only be configured in the properties of each user’s Active Directory account. This

may not be acceptable in most environments as this forces users to have their roaming profile for

every machine on the domain. Second, implementing user settings using Group Policy Objects

with a custom “ADM” template is not recommended as this method cannot modify

REG_BINARY registry values. Lastly, modifying the default user profile directly by mounting

the registry hive is also not recommended as some of the registry keys are overwritten on the first

logon.

User Profile Best Practices

Given that user-based registry settings are stored in the user’s profile, implementing these settings

relies on roaming profiles working optimally. The following best practices ensure that roaming

profiles perform well in your environment.

Use Service Pack 3. Make sure Windows XP Service Pack 3 in installed as there are at

least two bug fixes that resolve very slow login times. (If there is a firm requirement for

SP2, apply Microsoft hotfixes KB899409 and KB941158.)

Use Citrix Profile Management. There is no policy to set a roaming profile path with

Windows XP (Microsoft added this for Vista and later). The only other out-of-the-box

option is to configure the user’s profile (not Terminal Services Profile) in their Active

Directory user account properties, but this would affect the user’s profile for every

system they log into on the domain. This is not sufficient for most environments. Citrix

Profile Management allows administrators to tailor the profile configuration for the

desktop virtualization environment without impacting users when they are outside of the

environment. It can easily be added to a new or existing XenDesktop implementation

and is fully configurable using Group Policy.

http://blogs.technet.com/deploymentguys/archive/2009/10/29/configuring-default-user-settings-full-update-for-windows-7-and-windows-server-2008-r2.aspx




6

Install UPHClean. This trusted helper program helps ensure user profiles are unloaded

and saved to the network store correctly upon logoff. The latest release of this software

is version 1.6d and can be downloaded from Microsoft’s website. This version only

supports 32-bit operating systems, though. Version 2.0 beta, which is also available,

works with 64-bit operating systems, but this version is in permanent beta as UPHClean

is now an abandoned project. (The functionality of UPHClean is included in Windows

Vista and later.)

Ensure KB941158 is Applied. Although KB941158 is supposed to be included in

Windows XP Service Pack 3, the iedkcs32.dll file is not updated properly in some

environments. Verify the version of this file in the %WINDIR%\system32 folder and

ensure it is at least 17.0.6000.20668. If not, the updated version of the file can be found

in a nested windows directory by using Windows search. Copy the updated version to

the %WINDIR%\system32 and %WINDIR%\system32\dllcache folders. Once the

iedkcs32.dll file is updated, the fix must then be enabled by adding the registry key

documented in Microsoft Knowledge Base article KB941158. This fix may not be

needed if using Internet Explorer 6 or earlier.

Do Not Modify or Replace the Default User Profile. While this shortcut of applying

registry changes to future users may be easy to implement, it is explicitly unsupported by

Microsoft and can cause unexplained permissions and user profile path issues. A more

advantageous approach is to leverage group policy preferences or a logon script to update

only the appropriate registry keys and values. See the preceding section for more details.

Use Userenv and Profile Management Logging. If logon times are longer than

expected, enable all Userenv and Profile Management logging facilities. Look for long

delays during the logon process as potential culprits. By default, both of these write to

the system drive. If a standard mode vDisk image is used, the desktop must not be

rebooted or the log files will be deleted. Once troubleshooting is finished, advanced

logging should be disabled. To enable userenv logging, see Microsoft Knowledge Base

article KB221833. To enable Profile Management logging, see the Citrix eDocs Library

article Setup Logging with Profile Management.

Recommended Configurations

The following registry changes are recommended for all deployment scenarios and would almost

always be desirable in a Windows XP hosted VM-based VDI desktop implementation.

Configuration Registry Modification (in REG file format)

Force Offscreen

Composition for Internet

Explorer

[HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main]

"Force Offscreen Composition"=dword:00000001

Reduce Menu Show Delay [HKEY_CURRENT_USER\Control Panel\Desktop]

"MenuShowDelay"="150"

http://support.microsoft.com/kb/941158

http://support.microsoft.com/kb/221833

http://support.citrix.com/proddocs/topic/user-profile-manager-den/upm-set-logging-den.html


7


Disable all Visual Effects

except "Use common

tasks in folders" and "Use

visual styles on windows

and buttons"

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\VisualEffects]

"VisualFXSetting"=dword:00000003

[HKEY_CURRENT_USER\Control Panel\Desktop\WindowMetrics]

"MinAnimate"="0"

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced]

"ListviewAlphaSelect"=dword:00000000

"TaskbarAnimations"=dword:00000000

"ListviewWatermark"=dword:00000000

"ListviewShadow"=dword:00000000

[HKEY_CURRENT_USER\Control Panel\Desktop]

"DragFullWindows"="0"

"FontSmoothing"="0"

"UserPreferencesMask"=hex:90,12,01,80

Disable Desktop Cleanup

Wizard

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer]

"NoDesktopCleanupWizard"=dword:00000001

Disable Auto Searching

Network Printers/Shares

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced]

"NoNetCrawling"=dword:00000001

Disable Screen Saver [HKEY_CURRENT_USER\Software\Policies\Microsoft\Windows\Control Panel\Desktop]

"ScreenSaveActive"="0"

Optional Configurations

This set of user-based registry configurations is optional. In many cases, these configurations

should be implemented; however, these configurations should be analyzed for suitability to each

unique environment.


Disable Windows Sounds [HKEY_CURRENT_USER\AppEvents\Schemes]

@=".None"

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\.Default\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\AppGPFault\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\CCSelect\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\Close\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\DeviceConnect\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\DeviceDisconnect\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\DeviceFail\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\Maximize\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\MenuCommand\.Current]


8


@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\MenuPopup\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\Minimize\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\Open\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\RestoreDown\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\RestoreUp\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\ShowBand\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\SystemAsterisk\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\SystemExclamation\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\SystemExit\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\SystemHand\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\SystemNotification\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\SystemQuestion\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\SystemStart\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\WindowsLogoff\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\WindowsLogon\.Current]

@=""

[HKEY_CURRENT_USER\AppEvents\Schemes\Apps\Explorer\Navigating\.Current]

@=""

Set Screensaver to Blank [HKEY_CURRENT_USER\Software\Policies\Microsoft\Windows\Control Panel\Desktop]

"SCRNSAVE.EXE"="scrnsave.scr"

Remove Language Bar

(Disable Advanced Text

Services)

[HKEY_CURRENT_USER\Software\Microsoft\CTF]

"Disable Thread Input Manager"=dword:00000001

Remove Shut Down

option from Start Menu

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer]

"NoClose"=dword:00000001

Reduce Cursor Blink Rate [HKEY_CURRENT_USER\Control Panel\Desktop]

"CursorBlinkRate"="795"


9

Conclusion

While XenDesktop is designed to work great out of the box with Windows XP, there are still many

ways to optimize Windows XP further in terms of user experience and system performance. Every

good system implementation must have a level of optimization to utilize the resources in the best

manner possible. By applying this thinking to the Windows XP image, the user should have a better

computing experience while having a smaller impact on the underlying infrastructure.


10

Revision History

Revision Change Description Updated By Date

0.1 Initial Draft Kevin Bacon 1/15/2010

0.2 Review Michael Schaeffer 2/01/2010

0.3 Review Daniel Feller / Michael Bogobowicz 2/04/2010

1.0 Final Kevin Bacon 2/06/2010

Citrix Consulting - Americas

Citrix Systems, Inc.

851 W Cypress Creek Road

Fort Lauderdale, FL 33309 USA

Phone: 1-800-393-1888 Option 55

Phone: 1-954-229-6170

Citrix Consulting - Pacific

Citrix Systems Singapore Pte Ltd

8, Temasek Boulevard

#34-02, Suntec Tower 3

Singapore, 038988

Singapore

Citrix Consulting - Europe

Citrix Systems UK, Ltd.

Chalfont House

Chalfont Park, Gerrards Cross

Bucks SL9 0BG

Phone: +44 1753-276-200

Citrix Systems Japan KK

Kasumigaseki Common Gate West Tower 24F

3-2-1, Kasumigaseki, Chiyoda-ku

Tokyo, 100-0013 Japan

About Citrix

Citrix Systems, Inc. (NASDAQ:CTXS) is the leading provider of virtualization, networking and software as a service

technologies for more than 230,000 organizations worldwide. Its Citrix Delivery Center, Citrix Cloud Center (C3) and

Citrix Online Services product families radically simplify computing for millions of users, delivering applications as an

on-demand service to any user, in any location on any device. Citrix customers include the world’s largest Internet

companies, 99 percent of Fortune Global 500 enterprises, and hundreds of thousands of small businesses and prosumers

worldwide. Citrix partners with over 10,000 companies worldwide in more than 100 countries. Founded in 1989, annual

revenue in 2008 was $1.6 billion.

©2009 Citrix Systems, Inc. All rights reserved. Citrix®, Access Gateway™, Branch Repeater™, Citrix Repeater™,

HDX™, XenServer™, XenApp™, XenDesktop™ and Citrix Delivery Center™ are trademarks of Citrix Systems, Inc.

and/or one or more of its subsidiaries, and may be registered in the United States Patent and Trademark Office and in

other countries. All other trademarks and registered trademarks are property of their respective owners.

Optimizing Windows XP for XenDesktop - · Consulting first addressed this topic in a white paper...

Documents

Transcript of Optimizing Windows XP for XenDesktop - · Consulting first addressed this topic in a white paper...