Sean, Thanks for the quick response. I've made the suggested changes, but I'm afraid I am having the same problems. In fact, I see that a previous thread ( http://www.spinics.net/lists/linux-rdma/msg07573.html ) follows another user with the same problem. In fact, I finally found a message (from you, actually! http://www.spinics.net/lists/linux-rdma/msg07601.html ) saying that as of 2011, librdmacm can't handle UC. Is this still the case?
Thanks, Christopher On Wed, Feb 4, 2015 at 9:19 PM, Hefty, Sean <[email protected]> wrote: >> I have a fairly complex system that I've built over the last few years >> as part of my PhD that uses reliable connections for message-passing >> and RDMA. After reading a recent paper, I decided to compare the >> performance of message-passing over unreliable connections for the >> sake of completeness, but unfortunately, I've repeatedly run into >> obstacles trying to switch to using the UC mode. I even wrote a tiny >> client and server that simply opens a connection, sends a message, and >> sends a response, and when I switch from RC to UC, the rdma_accept() >> at the server always fails with EINVAL when trying to accept the >> client's rdma_connect(). I'm afraid documentation, source code, and >> experimentation have left me stymied. I have tried using RDMA_PS_IB >> and RDMA_PS_UDP instead of RDMA_PS_TCP in rdma_create_id() to no >> avail, I've experimented with qp_attr fields, and my MWE shows the >> same problems as the larger system. Any assistance woudl be greatly >> appreciated, and I'd be happy to provide more details about my setup >> of the event channel, queue pair, buffers, and so on if necessary. > > I believe you can get UC support by using the calls rdma_getaddrinfo and > rdma_create_ep, which allows you to specify the qp_type as IBV_QPT_UC. For > the port space, you will need RDMA_PS_IB. The TCP and UDP port spaces map to > QP types RC and UD, respectively. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
