[Cerowrt-devel] parsing tc statistical output

[Dave Taht]

I just wanted to note that fq_codel and related have a few interesting stats.

First important note: fq_codel as in the linux mainline, resets the
"dropped" statistic when a queue becomes new. cero preserves it. Eric
was making noises about removing dropped entirely due to the effect on
cacheline behavior, I'm planning on keeping it... and adding more
stats, actually! But if you parse dropped, only use the summary
dropped stat not the queue one.

Basic stats can be had via:

tc -s qdisc show dev your_device

Next up, on a busy system, doing a:

tc -s class show dev your_device

will actually show you the depth of your individual queues (those that
have any depth).

I will try to write up a wiki entry on what all those stats mean. At some point.

Lastly:
tc's output gets rapidly more complex and hard to parse with htb and
simple_qos or dan's scripts...