I have a need to refer back to the TCP tuning settings introduced recently by Microsoft, so I decided to put all of this in one place so that I can find them easier in the future.
To see the status of these settings, use: netsh int tcp show global
To enable receive side scaling: netsh int tcp set global rss=enabled
To enable chimney offload state: netsh int tcp set global chimney=enabled
To enable direct cache access (dca): netsh int tcp set global dca=enabled
To change the auto-tuning level: netsh int tcp set global autotuninglevel=normal
To change the congestion provider: netsh int tcp set global congestionprovider=ctcp
To change the ECN capability: netsh int tcp set global ecncapability=enabled
To change the timestamps: netsh int tcp set global timestamps=enabled
To change the setting for NetDMA:
To enable or disable NetDMA, follow these steps:
- Click Start, click Run, type regedit, and then click OK.
- Locate the following registry subkey, and then click it:: HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesTcpipParameters
- Double-click the EnableTCPA registry entry. Note If this registry entry does not exist, right-click Parameters, point to New, click DWORD Value, type EnableTCPA, and then press ENTER.
- To enable NetDMA, type 1 in the Value data box, and then click OK.
- To disable NetDMA, type 0 in the Value data box, and then click OK.
- If the EnableTCPA registry entry does not exist, enable the NetDMA functionality.
If you want to see the MTU applied to the connection: netsh interface ipv4 show subinterface
If you want to change the MTU: netsh interface ipv4 set subinterface "connection_name" mtu=9000 store=persistent
