References > Troubleshooting > Troubleshooting performance > Slow Performance on Windows Server 2008

Troubleshoot slow performance on Windows Server 2008

SAM supports Windows Server 2008 R2 only. Previous versions of Windows Server 2008 are no longer supported.

If SolarWinds is installed on Windows Server 2008 or Windows Vista and there are any devices on your network, between your SolarWinds server and your database server, that do not support RFC 1323, “TCP Extensions for High Performance.” The TCP window size auto-tuning feature of Windows Server 2008 and Windows Vista may prevent your SolarWinds server from successfully connecting with your Orion database. This TCP auto-tuning feature is intended as a network-sensitive restriction, applied by the receiver-your SolarWinds server-on the amount of data it is allowed or able to receive. If any devices along the network path between your SolarWinds server and your Orion database do not support the TCP window scaling detailed in RFC 1323, the allowed size of the TCP window in packets sent to your SolarWinds server may not match the TCP window size reported by packets sent from your SolarWinds server. This mismatch may lead to failed connections between your SolarWinds server and your Orion database. The following procedure disables this TCP auto-tuning feature, resetting the TCP receive window to 64kB.

You should disable TCP Auto-tuning:

  1. Click Start > All Programs > Accessories.
  2. Right-click Command Prompt, and then click Run as Administrator.
  3. If you are prompted by User Account Control, click Continue to open the elevated command prompt.

    In some cases, having User Account Control (UAC) enabled on Windows Server 2008 and Windows Vista (evaluation-only) can lead to installation errors. For more information about disabling UAC, see this KB article Disabling User Account Control (UAC).

  4. At the prompt, enter the following: netsh interface tcp set global autotuninglevel=disabled
  5. Close the command prompt window, and then restart your SolarWinds server.