> -----Original Message----- > From: lng-odp [mailto:lng-odp-boun...@lists.linaro.org] On Behalf Of EXT > Zoltan Kiss > Sent: Friday, January 29, 2016 2:13 PM > To: Elo, Matias (Nokia - FI/Espoo); EXT Ola Liljedahl > Cc: lng-odp@lists.linaro.org > Subject: Re: [lng-odp] [API-NEXT PATCH 00/11] DPDK pktio implementation > > > > On 29/01/16 08:19, Elo, Matias (Nokia - FI/Espoo) wrote: > > *From:*EXT Ola Liljedahl [mailto:ola.liljed...@linaro.org] > > *Sent:* Thursday, January 28, 2016 4:39 PM > > *To:* Elo, Matias (Nokia - FI/Espoo) <matias....@nokia.com> > > *Cc:* EXT Zoltan Kiss <zoltan.k...@linaro.org>; lng-odp@lists.linaro.org > > *Subject:* Re: [lng-odp] [API-NEXT PATCH 00/11] DPDK pktio > implementation > > > > On 28 January 2016 at 15:14, Elo, Matias (Nokia - FI/Espoo) > > <matias....@nokia.com <mailto:matias....@nokia.com>> wrote: > > > > > -----Original Message----- > > > From: EXT Zoltan Kiss [mailto:zoltan.k...@linaro.org > > <mailto:zoltan.k...@linaro.org>] > > > Sent: Thursday, January 28, 2016 3:21 PM > > > To: Elo, Matias (Nokia - FI/Espoo) <matias....@nokia.com > > <mailto:matias....@nokia.com>>; lng- > > > o...@lists.linaro.org <mailto:o...@lists.linaro.org> > > > Subject: Re: [lng-odp] [API-NEXT PATCH 00/11] DPDK pktio > > implementation > > > > > > Hi, > > > > > > On 28/01/16 07:03, Matias Elo wrote: > > > > The current unoptimized DPDK pktio implementation achieves > > forwarding rates > > > > (odp_l2fwd), which are comparable to netmap pktio and scale > > better with > > > larger > > > > thread counts. Some initial benchmark results below > > > > (odp_l2fwd 4 x 10 Gbps - 64B, Intel Xeon E5-2697v3). > > > > > > > > Threads > > > > 1 2 4 6 8 10 12 > > > > DPDK 6.7 12 25.3 37.2 47.6 47.3 > > 46.8 MPPS > > > > Netmap 6.1 12.6 25.8 32.4 38.9 38.6 > 38.4 > > > > > > My performance results for ODP-DPDK are unidirectional between > two > > > ports, where one thread does the actual work (the other is > > idling), in > > > that case it can achieve 14 Mpps. Is your number 6.7 Mpps > comparable > > > with this? > > > > These numbers are combined throughputs from all 4 ports. No > > "maintenance" > > thread is needed. With two ports and unidirectional traffic a single > > thread is able > > to handle about 7 MPPS. > > > > > Your main source of optimization seems to be to do zerocopy on RX > > side, > > > but it needs change in linux-generic buffer management: > > > - allow allocating zero length buffers, so you can append the > buffers > > > from the mbuf there > > > - release the mbufs during odp_packet_free(), that needs some > DPDK > > > specific code, a destructor which calls rte_pktmbuf_free() on the > > stored > > > pointers. > > > > > > But even with that there will be a cost of wrapping the mbuf's > into > > > linux-generic buffers, and you can't avoid copy on TX side. > > > > Yep, this is in my to-do list. > > > > Perhaps ODP linux-generic should use mbufs? I think that would allow for > > the greatest amount of friction-less coexistence. > > > > At first I’m going to try to use mbufs along ODP packets as Zoltan > > described. Moving to using only mbufs is a whole different conversation > > and may introduce a new set of problems. E.g. mbuf not supporting some > > features we require. Still, it’s an option we could think about. > > Using mbuf's is the key difference between this approach and ODP-DPDK. > The latter reuses most of the linux-generic code (including pktio now as > well), but it has its own buffer, packet(_flags) and pool implementation > which builds on DPDK mbuf's and mempool's. The linux-generic > implementation files are only kept there to make seamless git repo sync > possible. > If we plan to ditch the linux-generic implementations and use DPDK I'm > OK with that, but it would be good to know where should I put my efforts. >
There's lots of DPDK libraries to be utilized (e.g. rte_sched for TM, etc) by the odp-dpdk implementation. Odp-dpdk should utilize over time more dpdk libs and less linux-generic code. Linux-generic (I'd prefer odp-linux) will use DPDK only as another pktio. This is to ensure that we maintain low dependency to any external library (which is not part linux). Packet buffer format of odp-linux (when configured with --with-dpdk-path) could include storage space for mbuf and set pointers accordingly. So, that DPDK code would see mbufs and ODP code (other than the pktio) would see ODP packets. And both would access the data with zero copy. -Petri _______________________________________________ lng-odp mailing list lng-odp@lists.linaro.org https://lists.linaro.org/mailman/listinfo/lng-odp
