Connection Between the Oracle Client and Server Takes a Long time Due to the Windows 7 autotunning Function

1. The Oracle server uses Windows Server 2003 x64 OS, the database server uses Oracle Database 10, the client VM uses Windows s7 x86, and the database client uses sqlplus.

2. It takes one minute for a Windows 7 VM to connect to the server using the sqlplus; however, it takes only two seconds for a Windows XP VM to connect to the server using the sqlplus.

1. On the Windows 7 VM, choose Start > Run. In the Run dialog box, type cmd and press Enter. In the displayed window, run the following command:
netsh interface tcp set global autotuninglevel=disabled

2. Restart the VM.

1. The client and the server are communicated over the network; therefore, check the network first.

2. After the user sets the checksum offload property of the VM NIC to off, sets DNS IP address of the NIC to null, disables the netbios function of the NIC TCP/IP address, the fault persists.

3. Open https://www.google.com.hk/ and enter oracle slow windows 7, the following case is found: http://odenysenko.wordpress.com/2011/10/28/slow-oracle-net-from-windows-7vista/

The system functions of Windows 7 and Windows XP are a bit different. If this problem occurs on Windows 7, you can check such as faults occur on Windows XP.