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Date: Thu, 13 Feb 2025 09:01:23 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: Stanislav Fomichev <stfomichev@gmail.com>, davem@davemloft.net,
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 shuah@kernel.org, petrm@nvidia.com
Subject: Re: [PATCH net-next 3/3] selftests: drv-net: add a simple TSO test
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On Thu, 13 Feb 2025 11:02:51 -0500 Willem de Bruijn wrote:
> > > +        # Check that at least 90% of the data was sent as LSO packets.
> > > +        # System noise may cause false negatives, it is what it is.
> > > +        total_lso_wire  = len(buf) * 0.90 // cfg.dev["mtu"]
> > > +        total_lso_super = len(buf) * 0.90 // cfg.dev["tso_max_size"]  
> 
> Besides noise this also includes the payload to wire length with headers
> fudge factor, right?

Ah, fair point, up to 5% of header overhead here. I'll add that 
to the comment.