Thursday, May 23, 2013

InfiniBand/RDMA for Storage - SRP vs. iSER

by Sebastian Riemer (ProfitBricks GmbH)

Thursday, 23.05.2013, London II, 15:00-15:30 Uhr

InfiniBand (IB) originating 1999 has been used exclusively for HPC for a long time. The big advantages compared to conventional TCP/IP Ethernet are low latency and high bandwidth achieved by RDMA. Over time also RDMA over Ethernet has been evolved (iWARP, RoCE). As RDMA became cheaper, it is chosen for more and more Enterprise Data Centers as well. But these primarily need the storage protocols (e.g. SRP or iSER) instead of MPI.

The talk starts with an RDMA and RDMA hardware introduction. Then, it focuses on the downsides of RDMA like disruption upon congestion or the limited packet analysis possibility. The third part is about the required software (OFED) and the upper layer protocols (MPI, iSER, SRP, ...). And at the end the talk shows the current implementation state of the storage protocols iSER and SRP from the experience operating them in the ProfitBricks IaaS cloud.

The focused RDMA hardware is InfiniBand as it all began with InfiniBand.

About the author Sebastian Riemer:

Sebastian is a Linux kernel developer at ProfitBricks who develops storage solutions for the IaaS cloud. He is located in Berlin, Germany and joined ProfitBricks in 2011. At ProfitBricks he became InfiniBand (IB) specialist and gives the IB presentations. His custom patches can be found e.g. in SCST and SRP. In Israel he already met the whole storage team of Mellanox Technologies who are going for iSER. Sebastian started working with Linux and free software during his computer engineering studies in 2006.