Re: patch for duplicate tcp acks

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Fri, Apr 24, 2015 at 09:44:23PM +0000, Charlet, Ricky wrote:
> Howdy,
> 
>         I was suffering duplicate tpc acks.  It seems trivial to duplicate.... Any time I receive a non-zero len tcp packet, I ack it twice.  Note that I'm using a window scale of 3 and that may or may come into play.

Presumably this sent the stack on the far end into fast retransmit at least 50% more often
than it "should".  Did you actually see any performance problems associated with this?

I'm pretty sure I've seen this problem in the past, but at the time concluded that it
wasn't worth investigating because it seemed to have only the minor negative impact
of cluttering up my packet traces.  Which is not to say it should not be fixed!

Thanks!

Thor