While I'm not in the beta [jerks...] some friends are, and someone [let's call him 'Wyuli'] mentioned that the BitTorrent download was killing his computer. This sounded familiar, so I confirmed he was on XP and wrote up a little thing on the problem and how to alleviate the effects.
This is due to some crappy TCP/IP defaults in WinXP [I haven't run into a similar issue in Vista since they redid networking] that make your computer keep track of way more dead connection sockets than it needs to.
- open up regedit
- go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
- see if a key named 'TcpTimedWaitDelay' exists [it is not necessarily created by default]
- if it is not there create a new DWORD value with the above name and set it to 30 [decimal]
- if it ~is~ there just change it to 30.
- reboot
- ???
- PROFIT!
This option controls how long a connection sits in the TIME_WAIT state where either you or the other machine has closed the connection, but it stays in the TIME_WAIT state for the above number of seconds. While it is in TIME_WAIT the connection to that particular machine can be re-used a teensy bit faster than starting it from scratch, but the socket it occupies cannot be re-used until the TcpTimedWaitDelay expires.
By default in XP this is 2 minutes, which is a long *** time for something like BitTorrent that creates a squillion connections that might not last more than a few seconds each. This is especially apparent in large, active BT swarms. [ie. a few thousand people downloading a beta client] Setting the timeout to 30 seconds frees up the connections much faster in exchange for a performance hit that is somewhere between 'none' and 'imperceptible'. :P