Re: [PATCH v2 2/2] virtio-ring: Allocate indirect buffers from cachewhen possible

From: Michael S. Tsirkin
Date: Thu Sep 06 2012 - 04:44:02 EST


On Thu, Sep 06, 2012 at 05:27:23PM +0930, Rusty Russell wrote:
> "Michael S. Tsirkin" <mst@xxxxxxxxxx> writes:
> > Yes without checksum net core always linearizes packets, so yes it is
> > screwed.
> > For -net, skb always allocates space for 17 frags + linear part so
> > it seems sane to do same in virtio core, and allocate, for -net,
> > up to max_frags + 1 from cache.
> > We can adjust it: no _SG -> 2 otherwise 18.
>
> But I thought it used individual buffers these days?

Yes for receive, no for transmit. That's probably why
we should have the threshold per vq, not per device, BTW.

--
MST
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