On Tue, Nov 12, 2013 at 05:13:43PM -0800, Eric Dumazet wrote:

Note this pskb_trim() will reallocate/copy nskb head completely, since
nskb is a clone. (And increment page counts of frags, then eventually
decrement them)

I tested this patch one 'router', and it seems fine, although we consume
~90% more cpu doing the skb_segment() than not doing it.

I presume this is on a NIC that produces completely linear packets?
I wonder what happens if we don't convert head_frag to frags and just
use frag_lists like we used to?

Thanks,
-- 
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