Re: ????????? ?????????? ? TIME_WAIT ?? nginx

[CoolCold <coolcold@xxxxxxxxxxxx>]

Hello Leonid,

Tuesday, January 20, 2009, 7:41:24 PM, you wrote:

LP> На одном из серверов наблюдал странную картину. Из мира к nginx не более 
500 соединений. Но от nginx к apache более 2000, из которых почти все в 
TIME_WAIT. С чем это может быть связано? Нагрузки
LP> почти нету.
The design of TCP places the TIME-WAIT TCB at the endpoint that closes the 
connection; this decision conflicts with the semantics of many application 
protocols. The File Transfer Protocol (FTP)[4] and HTTP both interpret the 
closing of the transport connection as an end-of-transaction marker. In each 
case, the application protocol requires that servers close the transport 
connection, and the transport protocol requires that servers incur a memory 
cost if they do. Protocols that use other methods of marking 
end-of-transaction, e.g., SUN RPC over TCP[5], can have the clients close 
connections at the expense of a more complex application protocol.

from http://www.isi.edu/touch/pubs/infocomm99/infocomm99-web/


http://forums.theplanet.com/lofiversion/index.php/t62399.html

3.2  Closing and Reopening a Connection

      When a TCP connection is closed, a delay of 2*MSL in TIME-WAIT
      state ties up the socket pair for 4 minutes (see Section 3.5 of
      [Postel81].  Applications built upon TCP that close one connection
      and open a new one (e.g., an FTP data transfer connection using
      Stream mode) must choose a new socket pair each time.

from http://www.faqs.org/rfcs/rfc1185.html

np: none

Best regards,
CoolCold [COOLCOLD-RIPN]