GVC: Degraded Internet throughput from local ISP even though connected in Split tunnel

04/23/2020 34 2735

DESCRIPTION:

This article covers the throughput issue going drastically down with GVC software connected even though GVC is configured to use split tunneling.
In few scenarios, the issue persists even after disconnecting the GVC, the throughput is not restored until the PC is rebooted.

CAUSE:

The issue was identified by the Microsoft team on the specific build of the Windows 10 operating system related to the Receive Segment Coalescing (RSC) on the network adapter.

Reference Link:

https://answers.microsoft.com/en-us/windows/forum/windows_10-networking/wifi-issues-with-creators-update/4a20ba4f-33dc-4397-9823-e12dcb2607ba?auth=1

RESOLUTION:

New patch files of Windows 10 have been released which take care of the issue hence either you may upgrade the windows operating system to the latest patch available or perform the following workaround:

• Open an admin command prompt window:
  
  Start > All Apps > Windows System -> Right-click "Command Prompt" > More > Run as administrator
  
  
• Get your network adapter name:
  
  powershell Get-NetAdapter
  
  
• Note your adapter's name
  
  
  
• Get your network adapter "Receive segment coalescing" (Rsc) settings:
  
  powershell Get-NetAdapterRsc
  
  
  
• Disable Rsc for your network adapter:
  
  powershell Disable-NetAdapterRsc -Name ADAPTER_NAME_FROM_BEFORE
  
  .

  TIP: Be sure to replace ADAPTER_NAME_FROM_BEFORE with whatever your network adapter name is, without quotes.

  
  
  
• Verify Rsc is disabled for ipv4 and ipv6, on your network adapter:
  
  powershell Get-NetAdapterRsc
  
  Should now show IPv4Enabled False, and IPv6Enabled False, for your network adapter.
  
  
  
• Re-test your Internet connection.