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. 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 :) 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. 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
