-----Original Message----- From: Daniel Stenberg [mailto:[email protected]] Sent: Dienstag, 13. Oktober 2009 05:33 To: libcurl development Subject: Re: cleanup half closed sockets in connection cache
On Mon, 12 Oct 2009, Frank Meier wrote: > I now liked to change that behavior, and didn't find a nice solution. First > I wanted to remeber the sockets and then close it if I see that the socket > has been closed by the peer. but this would bypass libcurl, and imho would > be a hack. After further searching I've found a posting in this mailing > list, dealing with a similiar problem: > http://curl.haxx.se/mail/lib-2009-03/0009.html the patch included in this > post removed all connections in close_wait before a new request And that patch is merged into the main code since about that time. > but still there will be at least one (the last) connection, that will remain > in close_wait state "forever". So you're actually thinking it is worth adding an entirely new function and code in your app to call that function with some interval just to make sure there's a single socket being closed correctly? I personally do not. I would rather prefer to see that scanning to be done possibly on some other event and not only when adding a new connection, so that the possibility that it gets discovered and closed increases but without adding anything new to the API and without doing the check too often. -- / daniel.haxx.se > So you're actually thinking it is worth adding an entirely new function and > code in your app to call that function with some interval just to make sure > there's a single socket being closed correctly? I think there should be a possibility to handle this problem, even it it not a big one. Btw in our case we have an application with a lot of handler child processes, which leads to a lot of half open connections in the system (seen with netstat for example). Nevertheless I see your point, having an extra API call to handle this seems to be a not really generic approach. Another idea came to my mind, if it might be possible to use the curl_multi_socket_action() call to tell libcurl that something has happened on a socket under its control, and then lib curl checks the state of the socket and closes it if its half open. I tried this out, with no effect: I suppervised the socket in my application (poll) and then called curl_multi_socket_action(). I haven't had time to go any further in this direction (check libcurl code etc) but maybe this would be possible with a small modification. What do you think of that? cheers Franky ------------------------------------------------------------------- List admin: http://cool.haxx.se/list/listinfo/curl-library Etiquette: http://curl.haxx.se/mail/etiquette.html
