On Fri, May 10, 2024 at 01:11:49PM +0200, Jiri Pirko wrote: > Fri, May 10, 2024 at 12:52:52PM CEST, mst@xxxxxxxxxx wrote: > >On Fri, May 10, 2024 at 12:37:15PM +0200, Jiri Pirko wrote: > >> Thu, May 09, 2024 at 04:28:12PM CEST, mst@xxxxxxxxxx wrote: > >> >On Thu, May 09, 2024 at 03:31:56PM +0200, Jiri Pirko wrote: > >> >> Thu, May 09, 2024 at 02:41:39PM CEST, mst@xxxxxxxxxx wrote: > >> >> >On Thu, May 09, 2024 at 01:46:15PM +0200, Jiri Pirko wrote: > >> >> >> From: Jiri Pirko <jiri@xxxxxxxxxx> > >> >> >> > >> >> >> Add support for Byte Queue Limits (BQL). > >> >> >> > >> >> >> Signed-off-by: Jiri Pirko <jiri@xxxxxxxxxx> > >> >> > > >> >> >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@xxxxxxxxxx/ > > > > > >A quick search on lore turned up this, for example: > >https://lore.kernel.org/all/a11eee78-b2a1-3dbc-4821-b5f4bfaae819@xxxxxxxxx/ > > Says: > "Note that NIC with many TX queues make BQL almost useless, only adding extra > overhead." > > But virtio can have one tx queue, I guess that could be quite common > configuration in lot of deployments. Not sure we should worry about performance for these though. What I am saying is this should come with some benchmarking results. > > > > > > > > > > >> 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 > >> > > >
