Subject: Re: tx_queue_len question

From: Jarek Poplawski <[email-masked]>
Date: Wed, 1 Apr 2009 11:16:33 +0000

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.