> -----Original Message----- > From: linux-rdma-ow...@vger.kernel.org [mailto:linux-rdma- > ow...@vger.kernel.org] On Behalf Of Hiroyuki Sato > Sent: Monday, July 02, 2012 7:20 PM > To: linux-rdma > Subject: [Q] How to tranfer a file which is over 2GB(2^31) size in RDMA > network? > > Dear developers. > > I'm writing simple file transfer program. > > I would like to know about the following. > Q: How to tranfer a file which is over 2GB(2^31) size in RDMA network? > > Please imagine to transfer whole DVD(4.7GB) file via RDMA networok. > > The maximum message size of RC is 2^31. > so I can't transfer it with one RDMA message. > > Maybe It must split multiple parts. > When I sent first part with the following sequence, how to transfer second > part? > > Do I have to call qp ibv_destroy_qp and recreate new qp? > Or can I reuse current qp? > You can use the same QP to send multiple messages of same or different size. Receive side needs to have sufficient memory to receive 2GB of data, which you should have posted using post_recv(). Since you are going to divide a file/consumer application data to multiple RDMA messages, make sure sender and receiver agrees to a message size of interest. This is the simplest way to do via RDMA_SEND and RECV buffers.
You can further do it via sharing the stag before invoking post_send/recv and use RDMA Write or READ operations and don't need to synchronize the message size. Sender can send/split data into one or more WRITE messages followed by ending it with write_immidiate or send_immidiate to notify the peer of file transfer done. In a third way, you can void writing the application and use SDP protocol to send your file via FTP/SFTP, in which FTP server and client application sockets use the SDP sockets instead of TCP sockets. > I'm looking for similar example but I can't find it. > Any information is welcome. > > Thank you for your advice. > > Sincerely > > -- > Hiroyuki Sato. > > > File transfer sequence (1st part) > > ibv_open_device > ibv_alloc_pd > ibv_reg_mr > ibv_create_cq > ibv_create_qp > ibv_modify_qp(RESET->INIT) > ibv_post_recv > exchange lid, sid,qpn > ibv_connect > ibv_modify_qp(INIT->RTR) > ibv_modify_qp(RTR->RTS) > ibv_post_send > ... > > > > Environment > OS Scientific Linux 6.2 > OFED: 1.5.4.1 > > -- > Hiroyuki Sato > -- > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the > body of a message to majord...@vger.kernel.org More majordomo info at > http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
