On Mon, Feb 10, 2020 at 12:36:02PM -0500, Dennis Dalessandro wrote: > On 2/10/2020 8:31 AM, Jason Gunthorpe wrote: > > On Mon, Feb 10, 2020 at 08:18:05AM -0500, Dennis Dalessandro wrote: > > > This patch series is an accelerated ipoib using the rdma netdev mechanism > > > already present in ipoib. A new device capability bit, > > > IB_DEVICE_RDMA_NETDEV_OPA, triggers ipoib to create a datagram QP using the > > > IB_QP_CREATE_NETDEV_USE. > > > > > > The highlights include: > > > - Sharing send and receive resources with VNIC > > > - Allows for switching between connected mode and datagram mode > > > > There is still value in connected mode? > > It's really a compatibility thing. If someone wants to change modes that > will work. There won't be any benefit to connected mode though. The goal is > just to not break. I am a bit confused by this.. I thought the mlx5 implementation already could select connected mode? Why were core ipoib changes needed? > > > The patches are fully bisectable and stepwise implement the capability. > > > > This is alot of code to send without a performance > > justification.. What is it? Is it worth while? > > It avoids the scalability problem of connected mode, the number of QPs. > Incoming packets are spread into multiple receive contexts increasing > parallelism. The MTU is increased to allows 10K. It also reduces/removes the > verbs TX overhead by allowing packets to be sent through the SDMA engines > directly. No numbers to share? Jason
