919f9296   
   From: lynn@garlic.com   
      
   David Schwartz  writes:   
   > Exactly. You're very unlikely to overcome the fact that TCP has been   
   > worked out by protocol experts and implemented in each operating   
   > system by experts on that particular platform.   
   >   
   > The only time UDP wins over TCP is when TCP has an expensive feature   
   > that the particular application does not need. For example, if you   
   > don't need retransmissions, for example, it can be a big win to use   
   > UDP.   
      
   this was such a problem for 6-12 months in mid-90s.   
      
   one of the things was TCP session involves a minimum of 7 packet   
   exchange ... and keeps FINWAIT list for dangling session packets. TCP   
   session were assumed to be long-lived ... and session close was   
   relatively infrequent activity with FINWAIT list very short. As a   
   result, there was linear search of the FINWAIT list for incoming   
   packets.   
      
   HTTP behavior use of TCP/IP ... was more packet-like (UDP) than   
   session-like (TCP) ... and loaded webservers were starting to see   
   thousands on the FINWAIT list ... and spending 95% of processor time   
   doing FINWAIT list search. Big websites couldn't add machines fast   
   enough to handle the processing requirement. It took a little time for   
   vendors to come out with new release that completely redid FINWAIT list   
   handling and significantly reduced that overhead.   
      
   --   
   40+yrs virtualization experience (since Jan68), online at home since Mar1970   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)