> -----Original Message----- > From: Jerin Jacob <jerinjac...@gmail.com> > Sent: Thursday, November 5, 2020 3:15 PM > To: Rong, Leyi <leyi.r...@intel.com> > Cc: David Marchand <david.march...@redhat.com>; Zhang, Qi Z > <qi.z.zh...@intel.com>; dev <dev@dpdk.org> > Subject: Re: [dpdk-dev] [PATCH] examples/l3fwd: enable multiple Tx queues on > a lcore > > On Wed, Nov 4, 2020 at 2:34 PM Rong, Leyi <leyi.r...@intel.com> wrote: > > > > > > > -----Original Message----- > > > From: David Marchand <david.march...@redhat.com> > > > Sent: Wednesday, November 4, 2020 4:43 PM > > > To: Rong, Leyi <leyi.r...@intel.com> > > > Cc: Zhang, Qi Z <qi.z.zh...@intel.com>; dev <dev@dpdk.org> > > > Subject: Re: [PATCH] examples/l3fwd: enable multiple Tx queues on a > > > lcore > > > > > > On Wed, Nov 4, 2020 at 9:34 AM Rong, Leyi <leyi.r...@intel.com> wrote: > > > > > -----Original Message----- > > > > > From: David Marchand <david.march...@redhat.com> > > > > > Sent: Wednesday, November 4, 2020 4:14 PM > > > > > To: Rong, Leyi <leyi.r...@intel.com> > > > > > Cc: Zhang, Qi Z <qi.z.zh...@intel.com>; dev <dev@dpdk.org> > > > > > Subject: Re: [PATCH] examples/l3fwd: enable multiple Tx queues > > > > > on a lcore > > > > > > > > > > If I count well, this is the v3 of the patch. > > > > > Please version your patches. > > > > > > > > The previous versions are set to superseded. As nothing changes > > > > with content on those versions, can start from this version? > > > > > > The commitlog changes even if the code itself did not change, so > > > this is a different patch. > > > Different patches mean different versions. > > > This shows that some work happened since the v1 submission. > > > > > > > Agreed. > > > > > > > As there always has thoughput limit for per queue, on some > > > > performance test case by using l3fwd, the result will limited by > > > > the per queue thoughput limit. With multiple Tx queue enabled, the > > > > per queue thoughput > > > limit can be eliminated if the CPU core is not the bottleneck. > > > > > > Ah interesting. > > > Which nic has such limitations? > > > How much of an improvement can be expected from this? > > > > > > > > > -- > > > David Marchand > > > > The initial found was on XXV710 25Gb NIC, but suppose such issue can > > happen on more NICs as the high-end CPU per core boundary is higher than > many NICs(except 100Gb and above) per queue performance boundary. > > The improvement can be about 1.8X with that case@1t2q. > > As far as I understand, the Current l3fwd Tx queue creation is like this: > If the app has N cores and M ports then l3fwd creates, N x M Tx queues in > total, > What will be new values based on this patch? >
Hi Jacob, Total queues number equals to queues per port multiply port number. Just take #l3fwd -l 5,6 -n 6 -- -p 0x3 --config '(0,0,5),(0,1,5),(1,0,6),(1,1,6)' as example, With this patch appied, totally 2x2=4 tx queues can be polled, while only 1x2=2 tx queues can be used before. > Does this patch has any regression in case the NIC queues able to cope up with > the throughput limit from CPU. > Regression test relevant with l3fwd passed with this patch, no obvious result drop on other cases. > > > > > Leyi > >
