I am using my Vista Ultimate machine primarily now for day-to-day work.. And everything is running quite smoothly to be honest. No crashes, no freezes, no spyware.. Everything is great.
I help manage SEVERAL servers across my WAN and use Remote Desktop to great effect. But, last week a new Server was added. I logged in with my trusty Remote desktop to start setting up an SFTP server. Only, this time everything was WAY WAY WAY Slow… I mean I was waiting a good thirty seconds between clicks. I thought it might be my connection so I logged off, ran some speed tests, logged into another server and everything was great. So, I logged back into the server in question. SLOW! What’s going on?? On a whim I tried to log in to the server from my XP machine… It was Super Speedy??
Remote Desktop 6.0 leverages a new feature called auto-tuning for the TCP/IP receive window that could be causing the trouble. What is auto-tuning for the TCP/IP receive window? Well, the new Microsoft TCP/IP stack supports Receive Window Auto-Tuning. Receive Window Auto-Tuning continually determines the optimal receive window size by measuring the bandwidth-delay product and the application retrieve rate, and adjusts the maximum receive window size based on changing network conditions.
In Vista, Receive Window Auto-Tuning enables TCP window scaling by default, allowing up to a 16 MB window size. As the data flows over the connection, the TCP/IP stack monitors the connection, measures the current bandwidth-delay product for the connection and the application receive rate, and adjusts the receive window size to optimize throughput. The new TCP/IP stack no longer uses the TCPWindowSize registry values which many third-party utilities used to “tweak”.
Receive Window Auto-Tuning has a number of benefits. It automatically determines the optimal receive window size on a per-connection basis. In Windows XP, the TCPWindowSize registry value applies to all connections. Applications no longer need to specify TCP window sizes through Windows Sockets options. And IT administrators no longer need to manually configure a TCP receive window size for specific computers.
This setting can be turned off in Vista. First open a command prompt (cmd) as Administrator.. It’s not good enough for your user to have Administrative privileges… Right click on the Icon and select “Run as Administrator”
Then when the command window opens type:
netsh interface tcp set global autotuninglevel=disabled
To re-enable this feature you need to type:
netsh interface tcp set global autotuninglevel=normal
Tom also says that in some cases you may need to type:
netsh interface tcp set global rss=disabled
But I did not have to.. The first command solved my problem immediately!!
This also makes this my Site of the Week! Because it was WAY handy, Go by and check it out.. Maybe Tom has some answers for you?
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