RDMA – Remote Direct Memory Access

Remote Direct Memory Access (RDMA) is a technology that allows data to be transferred between computers or systems over a network without involving the processors of the computers. Instead, RDMA enables data to be read from or written to the memory of one computer directly to another computer’s memory, bypassing the operating system and CPU overhead that would typically be involved in such data transfers.

RDMA is particularly useful in high-performance computing (HPC), data centers, and cloud computing environments where low-latency, high-throughput data transfer is critical. By offloading data transfer tasks from the CPU and operating system, RDMA can significantly reduce latency and improve overall system performance.

There are different implementations of RDMA, with InfiniBand and Ethernet-based RDMA over Converged Ethernet (RoCE) being two common examples. InfiniBand is a high-speed interconnect technology designed specifically for high-performance computing and RDMA, while RoCE enables RDMA over traditional Ethernet networks with the help of specialized network adapters and switches.

RDMA technology is used in various applications such as data analytics, machine learning, storage systems, and distributed computing frameworks to achieve better performance and scalability.