[dpdk-dev] [PATCH 0/9] mbuf: structure reorganization

[Bruce Richardson]

On Thu, Mar 30, 2017 at 02:02:36PM +0200, Olivier Matz wrote:
> On Thu, 30 Mar 2017 10:31:08 +0100, Bruce Richardson <bruce.richardson at intel.com> wrote:
> > On Wed, Mar 29, 2017 at 09:09:23PM +0100, Bruce Richardson wrote:
> > > On Wed, Mar 29, 2017 at 05:56:29PM +0200, Olivier Matz wrote:  
> > > > Hi,
> > > > 
> > > > Does anyone have any other comment on this series?
> > > > Can it be applied?
> > > > 
> > > > 
> > > > Thanks,
> > > > Olivier
> > > >   
> > > 
> > > I assume all driver maintainers have done performance analysis to check
> > > for regressions. Perhaps they can confirm this is the case.
> > > 
> > > 	/Bruce  
> > > >   
> > In the absence, of anyone else reporting performance numbers with this
> > patchset, I ran a single-thread testpmd test using 2 x 40G ports (i40e)
> > driver. With RX & TX descriptor ring sizes of 512 or above, I'm seeing a
> > fairly noticable performance drop. I still need to dig in more, e.g. do
> > an RFC2544 zero-loss test, and also bisect the patchset to see what
> > parts may be causing the problem.
> > 
> > Has anyone else tried any other drivers or systems to see what the perf
> > impact of this set may be?
> 
> I did, of course. I didn't see any noticeable performance drop on
> ixgbe (4 NICs, one port per NIC, 1 core). I can replay the test with
> current version.
> 
I had no doubt you did some perf testing! :-)

Perhaps the regression I see is limited to i40e driver. I've confirmed I
still see it with that driver in zero-loss tests, so next step is to try
and localise what change in the patchset is causing it.

Ideally, though, I think we should see acks or other comments from
driver maintainers at least confirming that they have tested. You cannot
be held responsible for testing every DPDK driver before you submit work
like this.

Regards,
/Bruce