Regards _Sugesh
> -----Original Message----- > From: Jesse Gross [mailto:je...@kernel.org] > Sent: Friday, May 6, 2016 1:58 AM > To: Chandran, Sugesh <sugesh.chand...@intel.com> > Cc: pravin shelar <pshe...@ovn.org>; ovs dev <dev@openvswitch.org> > Subject: Re: [ovs-dev] [PATCH v2] tunneling: Improving tunneling > performance using DPDK Rx checksum offloading feature. > > On Thu, May 5, 2016 at 1:26 AM, Chandran, Sugesh > <sugesh.chand...@intel.com> wrote: > >> -----Original Message----- > >> From: Jesse Gross [mailto:je...@kernel.org] > >> Sent: Wednesday, May 4, 2016 10:06 PM > >> To: Chandran, Sugesh <sugesh.chand...@intel.com> > >> Cc: pravin shelar <pshe...@ovn.org>; ovs dev <dev@openvswitch.org> > >> Subject: Re: [ovs-dev] [PATCH v2] tunneling: Improving tunneling > >> performance using DPDK Rx checksum offloading feature. > >> > >> On Wed, May 4, 2016 at 8:58 AM, Chandran, Sugesh > >> <sugesh.chand...@intel.com> wrote: > >> >> -----Original Message----- > >> >> From: Jesse Gross [mailto:je...@kernel.org] > >> >> Sent: Thursday, April 28, 2016 4:41 PM > >> >> To: Chandran, Sugesh <sugesh.chand...@intel.com> > >> >> Cc: pravin shelar <pshe...@ovn.org>; ovs dev > <dev@openvswitch.org> > >> >> Subject: Re: [ovs-dev] [PATCH v2] tunneling: Improving tunneling > >> >> performance using DPDK Rx checksum offloading feature. > >> > > >> >> That sounds great, thanks for following up. In the meantime, do > >> >> you have any plans for transmit side checksum offloading? > >> > [Sugesh] The vectorization on Tx side is getting disabled when DPDK > >> > Tx > >> checksum offload is enabled. This causes performance drop in OVS. > >> > However We don’t find any such impact when enabling Rx checksum > >> offloading(though this disables Rx vectorization). > >> > >> OK, I see. Does the drop in throughput cause performance to go below > >> the baseline even for UDP tunnels with checksum traffic? (I guess > >> small and large packets might have different results here.) Or is it > >> that it reduce performance for unrelated traffic? If it's the latter > >> case, can we find a way to use offloading conditionally? > > [Sugesh] We tested for 64 byte UDP packet stream and found that the > > performance is better when the offloading is turned off. This is for any > traffic through the port. > > DPDK doesn’t support conditional offloading for now. > > In other words DPDK can't do selective vector packet processing on a port. > > As far as I know there are some technical difficulties to enable > > offload + vectorization together in DPDK. > > My guess is the results might be different for larger packets since those > cases > will stress checksumming more and rx/tx routines less. > > In any case, I think this is an area that is worthwhile to continue > investigating. > My expectation is that tunneled packets with outer UDP checksums will be a > use case that is hit increasingly frequently with OVS DPDK - for example, OVN > will likely start exercising this soon. [Sugesh]Totally agreed, I will do PHY-PHY, PHY-TUNNEL-PHY tests with different size traffic streams(64 Byte, 512, 1024, 1500) when checksum enabled/disabled and see the impact. Is there any other traffic pattern/tests that we have to consider? _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
