Reducing Network Utilization
While many of these features can also be useful on a diskless system where the disk is actually on the network, using them decreases cache effectiveness and thereby increases network utilization. In an environment that is sensitive to network utilization, consider reducing the effect of these features by disabling them or adjusting their properties.
In particular, System Restore and Offline Folders are not useful on a diskless system and can be detrimental to the performance of Windows on a diskless system. Provisioning Services provides a clearer, more reliable, and simpler restore point than System Restore by simply rebooting the target device. Offline Folders cache network files — a feature that is not applicable to a system where all files are on the network.
- Offline Folders
- Event Logs
Configuring Windows features on a Standard vDisk
- Prepare a Standard Image vDisk for configuration.
- Shutdown all target devices that use the Standard Image vDisk.
- From the Console, change the Disk Access Mode to Private Image.
- Boot one target device.
- Configure one or more features.
- Prepare the Standard Image vDisk for use
- Shutdown the target device previously used to configure the vDisk.
- From the Console, change the Disk Access Mode to Standard Image.
- Boot one or more target devices.
Configuring the Recycle Bin
Disabling the Recycle Bin deletes files immediately. Consequently, the file system reuses respective disk sectors and cache entries sooner.
To configure the Recycle Bin:
- From the target device, or Windows Explorer, right click on the Recycle Bin.
- Select Properties.
- Select Global.
- Select from the following settings:
- Use one setting for all drives
- Do not move files to the Recycle Bin. Remove files immediately when deleted.
Configuring Offline Folders
The disabling of Offline Folders is strongly recommended to prevent Windows from caching network files on its local disk – a feature with no benefit to a diskless system. Configure this feature from the target device or Windows Group Policy.
- Open Windows Explorer.
- Select Tools>Folder Options.
- Select Offline Folders.
- Uncheck Enable Offline Folders.
To configure using the Windows Group Policy:
Object | User ConfigurationAdministrative TemplatesNetworkOffline Files |
---|---|
Policy
Setting |
Disable user configuration of offline files
Enabled |
Policy
Setting |
Synchronize all offline files before logging off Disabled |
Policy
Setting |
Prevent use of the Offline Files folder
Enabled |
Configuring Event Logs
Reduce the maximum size of the Application, Security, and System logs. Configure this feature using the target device or Windows Group Policy.
- Select Start>Settings>Control Panel.
- Open Administrative Tools>Event Viewer.
- Open the properties for each log.
- Set the Maximum log size to a relatively low value. Consider 512 kilobytes.
To configure using the Windows Group Policy:
On the domain controller, use the Microsoft Management Console with the Group Policy snap-in to configure the domain policies for the following object:
Object | Computer ConfigurationWindows SettingsEvent LogSettings for Event Logs |
---|---|
Policy
Setting |
Policy Maximum Application Log Size
Relatively low value. Consider 512 kilobytes. |
Policy
Setting |
Maximum Security Log Size Relatively low value. Consider 512 kilobyte. |
Policy
Setting |
Maximum System Log Size
Relatively low value. Consider 512 kilobytes. |
Configuring System Restore
The disabling of System Restore is strongly recommended to prevent Windows XP from storing any restore points that result in large disk files. Provisioning Services provides an inherent restore feature whenever the target device reboots.
- Select Start, then Control Panel.
- Open System.
- Select System Restore.
- Check Turn off System Restore.
Configuring Logical Prefetch
Disabling Logical Prefetcher prevents Windows XP from caching additional files.
To disable logical prefetcher, set the following registry value to 0 (zero):
HKLMSYSTEMCurrentControlSetControlSession ManagerMemory ManagementPrefetchParametersEnablePrefetcher
Configuring Automatic Disk Defragmentation
Disabling Automatic Disk Defragmentation prevents Windows XP from filling the vDisk write cache by automatically de-fragmenting the vDisk during boot time.
To disable automatic disk defragmentation, set the following registry key value data:
Key HKEY_LOCAL_MACHINEMicrosoftDfrgBootOptimizeFunction
Value Name Enable
Value Type REG_SZ
Value Data N
Disabling Windows Automatic Updates
If you have the Windows Automatic Updates service running on your target device, Windows periodically checks a Microsoft Web site and looks for security patches and system updates. If it finds updates that have not been installed, it attempts to download them and install them automatically. Normally, this is a useful feature for keeping your system up-to-date. However, in a Provisioning Services implementation using Standard Image mode, this feature can decrease performance, or even cause more severe problems. This is because the Windows Automatic Updates service downloads programs that fill the write cache. When using the target device’s RAM cache, filling the write cache can cause your target devices to stop responding.
Re-booting the target device clears both the target device and Provisioning Services write cache. Doing this after an auto-update means that the Automatic Updates changes are lost, which defeats the purpose of running Automatic Updates. (To make Windows updates permanent, you must apply them to a vDisk while it is in Private Image mode).
To prevent filling your write cache, make sure to disable the Windows Automatic Updates service for the target device used to build the vDisk.
- Select Start>Settings>Control Panel>Administrative Tools.
- Select System.
- Click the Automatic Updates tab.
- Select the Turn Off Automatic Updates radio button.
- Click Apply.
- Click OK.
- Select Services.
- Double-click the Automatic Updates service.
- Change the Startup Type by selecting Disabled from the drop-down list.
- If the Automatic Updates service is running, click the Stop button to stop the service.
- Click OK to save your changes.
- Shutdown all target devices that share the vDisk.
- Change the vDisk mode to Private image.
- Boot one target device from that vDisk.
- Apply Windows updates.
- Shutdown the target device.
- Change vDisk mode to Standard image.
- Boot all target devices that share this vDisk.