RE: [PATCH RFC v4 net-next 0/5] virtio_net: enabling tx interrupts
From: David Laight
Date: Tue Dec 02 2014 - 05:00:44 EST
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?