Stephen Hemminger wrote:
> I think this is a real problem, and was observed by Werner with umlsim.
> Don't know when it got introduced because it appears to pre-date the
> '04 work in adding Westwood, BIC, Vegas. Perhaps Alexey can shed some
> light on this.
If this is still the old cwnd quartering bug, then it's very very
old. Cheng Jin and I spotted it at the end of 2002 in 2.4.18, but
didn't look at earlier versions. (Later, I used this problem to
demonstrate how to fix bugs on the fly in umlsim.)
You can find the whole discussion in the following two threads:
Note that the fix isn't trivial (or, at least, it wasn't when we
looked at it), because just eliminating the /2 would make us too
aggressive in another, even weirder case, as I've described in
(which I admit to be somewhat daunting reading).
Recently, I noticed that my umlsim-based "hotfix" wouldn't improve
things in recent kernels anymore. I thought "cool, someone finally
sat down and fixed it", but perhaps that was premature.
/ Werner Almesberger, Buenos Aires, Argentina werner@xxxxxxxxxxxxxxx /