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SubjectRe: NETIF_F_SG question
Date
> Joakim Tjernlund wrote:
> > I am thinking of implementing harware scatter/gatter support( NETIF_F_SG) in my
> > ethernet driver. The network device cannot do HW checksuming.
> >
> > Will the IP stack make use of the SG support and will there be any significant performance
> > improvement?
>
>
> No; you need HW checksumming for NETIF_F_SG to be useful.
>
> If HW checksumming is not available, scatter-gather is useless, because
> the net stack must always make a pass over the data to checksum it.
> Since it must do that, it can linearize the skb at the same time,
> eliminating the need for SG.
>
> Jeff

linearize = copy small buffers inte one big buffer, or?
Surley the copy operation will cost something?

Jocke
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