Re: [LARTC] CBQ_bandwidth

[Stef Coene <stef.coene@docum.org>]

On Wednesday 20 August 2003 12:50, Raghuveer wrote:
> Hi Stef,
>
> Reffering to page < http://www.docum.org/stef.coene/qos/faq/cache/7.html
>
>  > I found a para as follows,
>
> " CBQ is not always as accurate as it should be. See docum.org on the
> test page for some tests with bounded classes. The algorithm used by cbq
> is very "link sensitive". It calculates the link idle time and for that
> it needs the real link bandwidth, average packet size and some other
> parameters. But there calculations are not always accurate. So it's
> possible that you will get inaccurate results if you use CBQ to limit
> the traffic in a class.  "
>
> Here Iam slightly confused with real link bandwidth, Can I understand
> that while creating CBQ we need interface bandwidth (ethtool, mii-diag)
> and and while assigning the classes real link bandwidth is required. An
> example will definately help me. Can you pls suggest a way to find real
> link bandwidth....? As ethtool and mii-diag will only get the interface
> bandwidth.
The bandwidth parameter is the real link bandwidth like ethtook or mii-diag 
will show you.
If you want to limit all traffic to the link bandwidth, you have to create a 
class that's bounded and with rate = link bandwidth.  You can create 
non-bounded sub classes but the bandwidth will be limit by the bounded class 
to the link bandwidth.

Stef

-- 

stef.coene@docum.org
 "Using Linux as bandwidth manager"
     http://www.docum.org/
     #lartc @ irc.oftc.net

_______________________________________________
LARTC mailing list / LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/