On 11 Apr 2007, at 23:45, Ian McDonald wrote:
On 4/12/07, Gerrit Renker <gerrit@xxxxxxxxxxxxxx> wrote:
There is no way to stop a Linux CCID3 sender from ramping X up to
the link bandwidth of 1 Gbit/sec; but the scheduler can only
control packet pacing up to a rate of s * HZ bytes per second.
Let's start to think laterally about this. Many of the problems around
CCID3/TFRC implementation seem to be on local LANs and rtt is less
than t_gran. We get really badly affected by how we do x_recv etc and
the rate is basically all over the show. We get affected by send
credits and numerous other problems.
As a data point, we've seen similar stability issues with our user-
space TFRC implementation, although at somewhat larger RTTs (order of
a few milliseconds or less). We're still checking whether these are
bugs in our code, or issues with TFRC, but this may be a broader
issue than problems with the Linux DCCP implementation.
Colin
