Event ID 16712 — Advanced QoS Settings
Applies To: Windows Server 2008
Advanced Quality of Service (QoS) settings provide additional controls for IT administrators to manage computer network use and DSCP markings. Advanced QoS settings apply only at the computer level, whereas QoS policies can be applied at both the computer and user levels.
|Product:||Windows Operating System|
|Message:||QoS failed to read or set inbound TCP throughput level, error code: "%2".|
Correct TCP throughput level setting
Inbound TCP traffic controls the TCP bandwidth consumption on the receiving computer, whereas QoS policies affect outbound TCP and UDP traffic. By setting a lower throughput level on inbound TCP traffic, TCP will limit the size of its advertised TCP receive window. The effects of this setting are increased throughput rates and link utilization for other TCP connections that have higher bandwidths or latencies. By default, computers running Windows Vista and Windows Server 2008 are set to the maximum throughput level.
The TCP receive window has changed in Windows Vista and Windows Server 2008. Earlier versions of Windows limited the TCP receive window to a maximum of 64 kilobytes (KB), whereas Windows Vista and Windows Server 2008 dynamically size the TCP receive window up to 16 megabytes (MB). By using inbound TCP traffic control, you can control the inbound throughput level by setting the maximum value to which the TCP receive window can grow. The levels correspond to the following maximum values.
- 0=64 KB
- 1=256 KB
- 2=1 MB
- 3=16 MB
The actual TCP receive window size might be a value equal to or smaller than the maximum, depending on network conditions.
You must be logged on as an administrator or belong to the Administrators group to complete this procedure.
To set the TCP receive window:
- Click Start, click All Programs, click Accessories, right-click Command Prompt, click Run as administrator, click Continue, type gpedit, and then press ENTER.
- In Group Policy Management Editor, click Local Computer Policy, click Windows Settings, right-click Policy-based QoS, and then click Advanced QoS Settings.
- In TCP Receiving Throughput, select Configure TCP Receiving Throughput, and then select the level of throughput that you want.
Note: You can use Group Policy Management Console to change these settings on more than one computer.
To verify that the advanced QoS settings are being applied:
- Update Group Policy on your computer
- Confirm that the event does not appear in the event log
You must be logged on as an administrator or belong to the Administrators group to complete these procedures.
To verify the resolution of events related to QoS policies:
- Click Start, point to All Programs, click Accessories, right-click Command Prompt, click Run as administrator, and then click Continue.
- Type gpupdate /force, and then press** **ENTER to confirm that the event is no longer generated.
To view QoS events:
- Click Start, click Control Panel, click Administrative Tools, and then click Event Viewer.
- In the console tree, expand Windows Logs, and then click System.