On Mon, 03 Apr 2017 18:15:25 +0200 Thomas Monjalon <thomas.monja...@6wind.com> wrote:
> 2017-03-31 09:18, Ananyev, Konstantin: > > > On Fri, 31 Mar 2017 09:41:39 +0100, Bruce Richardson > > > <bruce.richard...@intel.com> wrote: > > > > On Fri, Mar 31, 2017 at 10:26:10AM +0200, Olivier Matz wrote: > > > > > I replayed my tests, and I can also see a performance loss > > > > > with 1c/1t (ixgbe), not in the same magnitude however. Here > > > > > is what I have in MPPS: > > > > > > > > > > 1c/1t 1c/2t > > > > > 53.3 58.7 current > > > > > 52.1 58.8 original patchset > > > > > 53.3 58.8 removed patches 3 and 9 > > > > > 53.1 58.7 with konstantin's patch > > > > > > > > > > So we have 2 options here: > > > > > > > > > > 1/ integrate Konstantin's patch in the patchset (thank you, > > > > > by the way) 2/ remove patch 3, and keep it for later until we > > > > > have something that really no impact > > > > > > > > > > I'd prefer 1/, knowing that the difference is really small in > > > > > terms of cycles per packet. > > > > > > > > > > > > > > 1 is certainly the more attractive option. However, I think we > > > > can afford to spend a little more time looking at this before > > > > we decide. I'll try and check out the perf numbers I get with > > > > i40e with Konstantin's patch today. We also need to double > > > > check the other possible issues he reported in his other > > > > emails. While I don't want this patchset held up for a long > > > > time, I think an extra 24/48 hours is probably needed on it. > > > > > > > > > > Yes, now that we have the "test momentum", try not to loose it ;) > > > > > > I'm guilty to have missed the performance loss, but honnestly, > > > I'm a bit sad that nobody tried to this patchset before (it > > > is available for more than 2 months), knowing this is probably > > > one of the most critical part of dpdk. I think we need to be > > > better next time. > > > > > > Anyway, thank you for your test and feedback now. > > > > I am also leaning towards option 1, but agree that some extra > > testing first need to be done before making the final decision. > > BTW, path #9 need to be removed anyway, even if will go for path #1. > > Konstantin > > Please, can we have a conclusion now? I think we sholuld go with proposition 1, I can resubmit an updated patch today. This rework is needed at least for metrics libraries. To summarize the perf data we have: - There is a small impact on Intel NICs (-0.4MPPS on ixgbe in iofwd mode according to Konstantin's test, which is less than 1%). I guess it can be optimized. - On mlx5, there is a gain (+0.8MPPS). - On sfc, there is also a gain. Any comment? Olivier
