tx_queue_len question

tx_queue_len question

[Miguel Ángel Álvarez]

Hi

Could anyone please tell me how tx_queue_len works? (Or where to take
a look to?).

I am facing two problems with it:
- Using ixp4xx_hss driver, I am not in the same situation if I let the
driver chose tx_queue_len in the initialization, or if I use ifconfig
with the same value (100). With the last it seems to be capable of
storing more frames.
- When I increment it to 300 using ifconfig, the behaviour seems to be
worse than in the case of 100 or 200. Which are the litis of the
value?

Thanks

Miguel Ángel Álvarez

Re: tx_queue_len question

[Jarek Poplawski]

On 30-03-2009 18:49, Miguel Ángel Álvarez wrote:
> Hi
> 
> Could anyone please tell me how tx_queue_len works? (Or where to take
> a look to?).

Maybe net/sched/sch_generic.c: pfifo_fast_enqueue()?

> 
> I am facing two problems with it:
> - Using ixp4xx_hss driver, I am not in the same situation if I let the
> driver chose tx_queue_len in the initialization, or if I use ifconfig
> with the same value (100). With the last it seems to be capable of
> storing more frames.

This shouldn't matter unless I miss something.

> - When I increment it to 300 using ifconfig, the behaviour seems to be
> worse than in the case of 100 or 200. Which are the litis of the
> value?

Except some special cases there is used a common value for a similar
class of devices, like in ether_setup(). The behaviour should depend
on the kind of traffic.

Jarek P.