On 2015/11/18 23:13, Kavanagh, Mark B wrote: >> On 2015/11/18 1:25, Flavio Leitner wrote: >>> On Wed, Nov 11, 2015 at 03:06:02PM +0000, Mark Kavanagh wrote: >>>> Add support for Jumbo Frames to DPDK-enabled port types, >>>> using single-segment-mbufs. >>>> >>>> Using this approach, the amount of memory allocated for each mbuf >>>> to store frame data is increased to a value greater than 1518B >>>> (typical Ethernet maximum frame length). The increased space >>>> available in the mbuf means that an entire Jumbo Frame can be carried >>>> in a single mbuf, as opposed to partitioning it across multiple mbuf >>>> segments. >>>> >>>> The amount of space allocated to each mbuf to hold frame data is >>>> defined by the user at compile time; if this frame length is not a >>>> multiple of the DPDK NIC driver's minimum Rx buffer length, the frame >>>> length is rounded up to the closest value that is. >>>> >>>> Signed-off-by: Mark Kavanagh <mark.b.kavan...@intel.com> >>>> --- >>>> INSTALL.DPDK.md | 67 ++++++++++++++++++++- >>>> lib/netdev-dpdk.c | 176 >>>> ++++++++++++++++++++++++++++++++++++++++++----------- >>>> 2 files changed, 207 insertions(+), 36 deletions(-) >>>> >>>> diff --git a/INSTALL.DPDK.md b/INSTALL.DPDK.md >>>> index 96b686c..9a30f88 100644 >>>> --- a/INSTALL.DPDK.md >>>> +++ b/INSTALL.DPDK.md >>>> @@ -859,10 +859,70 @@ by adding the following string: >>>> to <interface> sections of all network devices used by DPDK. Parameter 'N' >>>> determines how many queues can be used by the guest. >>>> >>>> + >>>> +Jumbo Frames >>>> +------------ >>>> + >>>> +Support for Jumbo Frames may be enabled at compile-time for DPDK-type >>>> ports. >>> It seems this could be dynamic and proportional to the MTU being used >>> by the port and not a compile-time option which depends on the NIC >>> hardware specs. Perhaps I am missing something. >> It make sense. >> >> And this patch really solve a big issue that when I transmit 1400 packet >> size, ovs-vsvitchd will return a "Bus error", although 1400 should not >> be a Jumbo frame. >> > Hi Michael, > > Thanks for your feedback; I'm glad to hear that the patch solved that issue > for you - I'm curious as to why you experience the Bus error for 1400B packet > though.
I'm debug for it now, seems DPDK has bug, I will find out who modified the mbuf address. > >> Mark, could it be an option when start vswitchd with dpdk, thus when >> users try to using Jumbo Frame, it will not need to re-compile ovs, just >> an advise :) >> > Agreed - I had intended to implement this functionality further down the > line, depending on how this patch was received. I'll add a runtime flag in v2. OK, Thanks > >> What's more, we could config it in run time, just like we dynamically >> config the queue numbers, but this has a lot work to do, it could be a >> further feature. > Do you mean the 'other_config: n-dpdk-rxqs' field in the Open_vSwitch table? > > I'm not sure how amenable a solution like this would be to the maintainers, > seeing as there is already an 'MTU' field present in the 'Interfaces' table. > Ben/Pravin - any thoughts as to supporting a separate MTU field for DPDK > interfaces? If there is MTU field in Interface, I think it OK, and no need to separate it. Just tell MTU to DPDK is OK. Thanks, Michael > Thanks, > Mark > >> Thanks, >> Michael >>> Thanks, >>> fbl >>> >>> _______________________________________________ >>> dev mailing list >>> dev@openvswitch.org >>> http://openvswitch.org/mailman/listinfo/dev >>> > _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
