Injong Rhee wrote:
Hi David and Stephen,
We tested this rate halving. In fact, rate having in fact degrades the
performance quite a bit. We can send you more information about it. Our test
indicates that this feature introduces many timeouts (because of bursts),
and also cause unnecessary cwnd backoff to reduce the transmission
unjustifiably low -- so there are many (I will repeat, many) window and
transmission oscillations during packet losses. We fix this problem
Could you point me to a paper or summary of your info?
completely using our own special burst control. It is very simple and easy
technique to implement. If you need some data to back up our claims, I will
send you more. Once we implemented our burst control, we don't have any
timeouts and not much fluctuation other than congestion control related.
Currently with rate having, current Linux tcp stack is full of hacks that in
fact, hurt the performance of linux tcp (sorry to say this). Our burst
control, in fact, simplifies a lot of that and makes sure cwnd to follow
very closely to whatever congestion control algorithm is intended it to
behave. The Linux Reno burst control in fact interferes with the original
congestion control (in fact, it tries to do its own), and its performance is
very hard to predict.
Can you characterize the workload/traffic/error rate that each
would be best suited for?
thanks,
Nivedita
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