svn commit: r232460 - user/andre/tcp_workqueue/sys/netinet

[Andre Oppermann]

Author: andre
Date: Sat Mar  3 13:31:20 2012
New Revision: 232460
URL: http://svn.freebsd.org/changeset/base/232460

Log:
  If the user has closed the socket then drop a persisting connection
  after a much reduced timeout.
  
  Typically web servers close their sockets quickly under the assumption
  that the TCP connections goes away as well.  That is not entirely true
  however.  If the peer closed the window we're going to wait for a long
  time with lots of data in the send buffer.

Modified:
  user/andre/tcp_workqueue/sys/netinet/tcp_timer.c

Modified: user/andre/tcp_workqueue/sys/netinet/tcp_timer.c
==============================================================================
--- user/andre/tcp_workqueue/sys/netinet/tcp_timer.c	Sat Mar  3 13:02:28 2012	(r232459)
+++ user/andre/tcp_workqueue/sys/netinet/tcp_timer.c	Sat Mar  3 13:31:20 2012	(r232460)
@@ -424,6 +424,16 @@ tcp_timer_persist(void *xtp)
 		tp = tcp_drop(tp, ETIMEDOUT);
 		goto out;
 	}
+	/*
+	 * If the user has closed the socket then drop a persisting
+	 * connection after a much reduced timeout.
+	 */
+	if (tp->t_state > TCPS_CLOSE_WAIT &&
+	    (ticks - tp->t_rcvtime) >= TCPTV_PERSMAX) {
+		TCPSTAT_INC(tcps_persistdrop);
+		tp = tcp_drop(tp, ETIMEDOUT);
+		goto out;
+	}
 	tcp_setpersist(tp);
 	tp->t_flags |= TF_FORCEDATA;
 	(void) tcp_output(tp);