http://cmangos.net/thread-576-post-3421.html#pid3421

"Suspecting it to be a timeout issue, I changed 10000 to 100000 in WorldSocketMgr.cpp (line 162 ACE_Time_Value interval(0, 10000); ) and the idle usage dropped to about 2%, and peaked at about 3% while logged in. The change did not seem to have an impact on latency or connection time." -Patman64