Two mechanisms enable offloading storage processes from the server CPU:
- RDMA (network protocol);
- ReFSv2 (accelerated VHDX operations).
RDMA (Read Direct Memory Access) is strongly recommended when implementing S2D solution. It enables reading the hosts memory thus bypassing the OS. The result is a reduction of CPU usage, a decrease of network latency and an increase in throughput.
ReFSv2 in Windows Server 2019 allows for accelerated VHDX operations. ReFSv2 works with metadata to maintain integrity. ReFSv2 also works with metadata when creating or extending virtual disks. Due to accelerated VHDX operations, ReFSv2 writes metadata instead of writing zeros as new blocks on disk. This results in an accelerated creation of a fixed VHDX and accelerated merging of checkpoints during data protection maintenance.