Re: problems with e1000 and jumboframes

[Evgeniy Polyakov]

On Thu, Aug 03, 2006 at 10:55:01PM -0700, David Miller (davem@xxxxxxxxxxxxx) wrote:
> From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
> Date: Fri, 04 Aug 2006 15:52:40 +1000
> 
> > Evgeniy Polyakov <johnpol@xxxxxxxxxxx> wrote:
> > > 
> > > But it does not support splitting them into page sized chunks, so it
> > > requires the whole jumbo frame allocation in one contiguous chunk, 9k
> > > will be transferred into 16k allocation (order 3), since SLAB uses
> > > power-of-2 allocation.
> > 
> > Actually order 3 is 32KB.

Yep, e1000 align 9k to 16k, then alloc_skb adds shared info and align it
to 32k.

> It's 64KB on my computer :)

Nice overhead...

-- 
	Evgeniy Polyakov
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