[Codel] sprout

[Kathleen Nichols]

Yes. I think that's a sort of "application - dependent" bit of code perhaps.
Van and I had various discussions about this and put that in with very
low bandwidth applications in mind, where some "maximums" might
be much smaller than others.

On 7/11/13 9:22 AM, Eric Dumazet wrote:
> On Thu, 2013-07-11 at 08:45 -0700, Kathleen Nichols wrote:
> 
>> Dave, not completely sure which reservation about maxpacket is in reference.
> 
> Hi Kathleen
> 
> I believe Dave is referring to the fact that we update maxpacket every
> time we dequeue a packet, and with GSO packet it makes little sense
> because after a while maxpacket is set to ~65535, the limit of the GSO
> packet size.
> 
> We might remove this code, and make maxpacket a constant.
> 
> diff --git a/include/net/codel.h b/include/net/codel.h
> index 389cf62..470e1ff 100644
> --- a/include/net/codel.h
> +++ b/include/net/codel.h
> @@ -170,7 +170,7 @@ static void codel_vars_init(struct codel_vars *vars)
>  
>  static void codel_stats_init(struct codel_stats *stats)
>  {
> -       stats->maxpacket = 256;
> +       stats->maxpacket = 1500;
>  }
>  
>  /*
> @@ -221,9 +221,6 @@ static bool codel_should_drop(const struct sk_buff *skb,
>         vars->ldelay = now - codel_get_enqueue_time(skb);
>         sch->qstats.backlog -= qdisc_pkt_len(skb);
>  
> -       if (unlikely(qdisc_pkt_len(skb) > stats->maxpacket))
> -               stats->maxpacket = qdisc_pkt_len(skb);
> -
>         if (codel_time_before(vars->ldelay, params->target) ||
>             sch->qstats.backlog <= stats->maxpacket) {
>                 /* went below - stay below for at least interval */
> 
> 
>