Our server is overloaded with TCP/IP sessions, we have 1200 - 1500 of them. Most of them are hanging in TIME_OUT state. It turns out that a connection in TIME_OUT state occupies a socket until 60 second time-out is elapsed.

The problem is that the server gets unresponsive and many clients are not getting served.

I have made a simple test: download an XML file from the server with Internet Explorer 8.0 The download finishes in a fraction of second. But then I see that the TCP/IP connection is hanging in TIME_OUT state for 60 seconds.

Is there any way to get rid of TIME_OUT waiting or make it less to free the socket for new connections?

I understand why TCP/IP connection enters TIME_OUT state, but I don't understand why Internet Explorer does not close the connection after the XML file download is over.

The details.

Our server runs web service written in Perl (mod-perl). The service provides weather data to clients. Client is a Flash appication (actually Flash ActiveX control embedded in Windows application).

OS: Ubuntu

Apache "Keep Alive" option is set to 0