Re: [PATCH net-next] tcp: add SNMP counter for the number of packets pruned from ofo queue

From: Yafang Shao
Date: Wed Jul 25 2018 - 10:00:44 EST


On Wed, Jul 25, 2018 at 9:55 PM, Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote:
>
>
> On 07/25/2018 06:40 AM, Yafang Shao wrote:
>
>>
>> Because we want to know why packets were dropped.
>> If that could be show in netstat, we could easily find that it is
>> dropped due to ofo prune.
>
>
> We have a counter already for these events : LINUX_MIB_OFOPRUNED
>
> You want to add another counter tracking number of _skbs_,
> which has no precise value for user,
> given each skb can contain a variable number of _packets_.
>

Got it.

But with LINUX_MIB_OFOPRUNED, we only know tcp_prune_ofo_queue is
called, but have no idea how many skbs are dropped.

Thanks
Yafang