On Thu, Jan 2, 2020 at 1:29 PM Jason Gunthorpe <jgg@xxxxxxxx> wrote: > > On Thu, Jan 02, 2020 at 09:47:06AM -0500, Terry Toole wrote: > > Hi, > > Is it possible to transfer a large file, say 25GB, between two computers using > > RDMA UD, and have an exact copy of the original file on the receiving side? My > > understanding is that the order of the messages is not guaranteed with UD. > > But I thought that if I only use one QP I could ensure that the ordering of the > > data will be predictable. > > It is not guaranteed to be in order. > > Why would you do this anyhow? The overhead to use RC is pretty small > So even if I am using only 1 QP, it is still not guaranteed to be in order. Ok. Thanks. The reason I am interested in doing this is that I am working on a project where we want to transfer data between an FPGA and a computer. Memory needs to be added on the FPGA side to buffer data for retries when RC is used. Adding memory makes the electronics on the sending side more complex. If we could transfer the data in UD mode, it may simplify other aspects of the project. Thanks again for your response, Terry
