From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] net: introduce netdevice gso_min_segs
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Date: Mon, 06 Oct 2014 17:54:10 -0400 (EDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Mon, 06 Oct 2014 14:42:58 -0700

> On Mon, 2014-10-06 at 17:21 -0400, David Miller wrote:
> 
>> So exactly what value are you using for mlx4?
>> 
> 
> It seems that on ConnectX-3 family, TSO packets of 2 or 3 MSS are not
> worth using TSO engine. The cutoff point seems to be 4 (same throughput)
> 
> So I was planning to use gso_min_segs = 4 only for them.
> 
>> Because I wonder if we should just generically forfeit TSO unless
>> we have > 2 segments, for example.
> 
> When I tested on bnx2x, this was not a gain.
> 
> bnx2x is faster sending TSO packets, even if they have 2 MSS.
> 
> I'll try the experiment on I40E Intel cards.

Ok I'm sold on your patch then if two major chipsets already benefit
from differing values.

I'll apply this, thanks Eric.