So, while doing some research on cable-modems yesterday, I discovered that they have notoriously large transmission buffers. Now, having previously determined that overlarge transmission buffers were bad, I set out to see what I could do about it.
Turns out that the answer is “a whole lot”.
There’s a Linux box running as a router. It connects to the cable-modem on eth0 and the rest of the local systems on eth1. Inbound bandwidth is 20Mbps, and outbound is 512Kbps.
Based on that, the answer was exactly one single command:
tc qdisc add dev eth0 root tbf rate 500kbit latency 50ms burst 1540
Bang. Instant performance improvement across the board. Smoother sharing of the cable-modem bandwidth, smoother downloads, better interactive response on remote hosts. It was really quite astonishing how much better it was right away.
Being that I’m a little pressed for time today, I’ll have to explain more later on (in part 2), but the short version is that this prevents any of your local hardware from jamming up network traffic in long queues.
More soon.
Update: Part 2 has been posted.
That sounds like an improvement, let us know if it does help in practice
It seriously improved things for me. All Internet access is better. Incidences of lag symptoms are hugely reduced.
Part 2 has been posted. See above.