about queue size

[Jeremie Le Hen]

Hi,

> How i can calculate (or best aproximate) queue size?

It depends on what you are targeting.  For example a big queue will
likely drop less packets than a small one but OTOH, this could
add a big latency because of numerous packets being queued.  Small
queues will drop more packets but latency will be reduced.

Generally I would advice to use small queues when used for interactive
traffic such as a ssh session or even HTTP requests.
IIRC big queues will maximize bandwidth, but some network guy may
precise these rules, I would be glad to.

The rules to compute queue sizes are deductible from the ipfw(8)
manual page, DUMMYNET section (see "queue {slots | sizeKbytes}").

Hope this helps.
Regards,
-- 
Jeremie Le Hen
< jeremie at le-hen dot org >< ttz at chchile dot org >