Re: [patch net-next] virtio_net: add support for Byte Queue Limits

Michael S. Tsirkin
2024-05-10T10:52:59Z

On Fri, May 10, 2024 at 12:37:15PM +0200, Jiri Pirko wrote:
> Thu, May 09, 2024 at 04:28:12PM CEST, mst@redhat.com wrote:
> >On Thu, May 09, 2024 at 03:31:56PM +0200, Jiri Pirko wrote:
> >> Thu, May 09, 2024 at 02:41:39PM CEST, mst@redhat.com wrote:
> >> >On Thu, May 09, 2024 at 01:46:15PM +0200, Jiri Pirko wrote:
> >> >> From: Jiri Pirko <jiri@nvidia.com>
> >> >>
> >> >> Add support for Byte Queue Limits (BQL).
> >> >>
> >> >> Signed-off-by: Jiri Pirko <jiri@nvidia.com>
> >> >
> >> >Can we get more detail on the benefits you observe etc?
> >> >Thanks!
> >>
> >> More info about the BQL in general is here:
> >> https://lwn.net/Articles/469652/
> >
> >I know about BQL in general. We discussed BQL for virtio in the past
> >mostly I got the feedback from net core maintainers that it likely won't
> >benefit virtio.
>
> Do you have some link to that, or is it this thread:
> https://lore.kernel.org/netdev/21384cb5-99a6-7431-1039-b356521e1bc3@redhat.com/

A quick search on lore turned up this, for example:
https://lore.kernel.org/all/a11eee78-b2a1-3dbc-4821-b5f4bfaae819@gmail.com/

> I don't see why virtio should be any different from other
> drivers/devices that benefit from bql. HOL blocking is the same here are
> everywhere.
>
> >
> >So I'm asking, what kind of benefit do you observe?
>
> I don't have measurements at hand, will attach them to v2.
>
> Thanks!
>
> >
> >--
> >MST
> >