Building on the new in-kernel iSCSI initiator stack released in FreeBSD 10.0 and the recently added iSCSI offload interface, Mellanox Technologies developed iSCSI extensions for RDMA (iSER) initiator support to enable efficient data movement using the hardware offload capabilities of Mellanox's 10, 40, 56 and 100 Gigabit IB/Ethernet adapters.

Remote Direct Memory Access (RDMA) has been shown to have a great value for storage applications. RDMA infrastructure provides benefits such as zero-copy, CPU offload, reliable transport, fabric consolidation, and many more. The iSER protocol eliminates some of the bottlenecks in the traditional iSCSI/TCP stack, provides low latency and high throughput, and is well suited for latency aware workloads.

This work includes a new ICL module that implements the iSER initiator. The iSCSI stack is slightly modified to support some extra features such as asynchronous IO completions, unmapped data buffers, and data-transfer offloads. The user will be able to choose iSER as the iSCSI transport with iscsictl.

The project is in the process of being merged to FreeBSD 11-CURRENT and is expected to ship with FreeBSD 11.0.