Post Syndicated from daroc original https://lwn.net/Articles/1074291/

How can cloud providers efficiently supply durable virtual block devices? Remote
Direct Memory Access (RDMA) provides a way for servers in a cluster to share
chunks of memory, but there still needs to be a protocol that operates on top of
RDMA to provide the guarantees expected of a block device. The kernel’s RDMA transport
library (RTRS) provides a way to send messages via RDMA. I
presented about two
new components built on top of RTRS at the 2026
Linux
Storage, Filesystem, Memory Management and BPF Summit: Reliable Multicast
over RTRS (RMR) and Block device over RMR (BRMR). These modules, which I
am working on with Jia Li, could be a way for cloud providers to
expose durable block devices with as little overhead as possible. To accomplish
that, however, we need some discussion and feedback from the community before
sending the modules upstream.