Re: [PATCH RFC v4 net-next 0/5] virtio_net: enabling tx interrupts

[Michael S. Tsirkin]

On Tue, Dec 02, 2014 at 10:00:06AM +0000, David Laight wrote:
> From: Jason Wang
> > > On Mon, Dec 01, 2014 at 06:17:03PM +0800, Jason Wang wrote:
> > >>  Hello:
> > >>
> > >>  We used to orphan packets before transmission for virtio-net. This
> > >> breaks
> > >>  socket accounting and can lead serveral functions won't work, e.g:
> > >>
> > >>  - Byte Queue Limit depends on tx completion nofication to work.
> > >>  - Packet Generator depends on tx completion nofication for the last
> > >>    transmitted packet to complete.
> > >>  - TCP Small Queue depends on proper accounting of sk_wmem_alloc to
> > >> work.
> > >>
> > >>  This series tries to solve the issue by enabling tx interrupts. To
> > >> minize
> > >>  the performance impacts of this, several optimizations were used:
> > >>
> > >>  - In guest side, virtqueue_enable_cb_delayed() was used to delay the tx
> > >>    interrupt untile 3/4 pending packets were sent.
> 
> Doesn't that give problems for intermittent transmits?
> 
> ...
> 
> 	David
> 

No because it has not effect in that case.

-- 
MST
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/