all network people please review this proposal: because someone is going to commit it soon. D5017

Ermal Luçi eri at
Wed Feb 1 01:04:53 UTC 2017

On Fri, Jan 20, 2017 at 7:15 AM, Slawa Olhovchenkov <slw at> wrote:

> On Fri, Jan 20, 2017 at 11:00:18PM +0800, Julian Elischer wrote:
> > Unless eri gets to it first I will.
> >
> > see
> >
> > If you have a server, you can put an arbitrary number of clients on
> > the same port number because they all have different addresses.
> >
> > However in the case of a client accessing multiple servers we are
> > limited to 65535 sessions because we strictly don't allow the same
> > port to be used more than once. This is silly because TCP is a
> > symmetrical protocol and of it works for the server it should work for
> > the client.
> >
> > So this patch changes the allocation of ports to allow the client to
> > use a port that has been used before as long as the previous port user
> > is not talking to the same host/port. This removes the limitation of a
> > freebsd machine being only capable of contacting 65000 hosts in a
> > single port shutdown timeout period. With modern machines capable of
> > initiating  MILLIONS of sessions per second, having a limitation of
> > 65000 per 2 minutes is a bit silly.
> >
> >
> > Please read the patch if you suspect this will have a bad effect of
> > any sort.  Once the session is started there is no record as to who
> > started it so any issues would have to be in the startup phase.
> Good.
> Can you use also destination port and source IP in same way as
> destination address?

This is an improvement over the proposal.
Let the existing proposal go in than can improve it even more.


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