Short for remote direct memory access: the lowest-latency networking in Azure, running over InfiniBand on HPC VM sizes whose names include an "r".
Also called remote direct memory access.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains RDMA in context, with comparison tables and the common traps.
Terms in this definition
- OVER
Gives a T-SQL window function its window: PARTITION BY, ORDER BY and, if wanted, a ROWS or RANGE frame. Rankings and running totals can then be worked out while every row is kept.
- HPC
Large-scale parallel computation, which Azure serves through CycleCloud or Azure Batch and VM sizes capable of RDMA.
Related terms
- Accelerated Networking
SR-IOV capability that cuts latency, jitter and CPU overhead for VM networking in Azure. HPC VM sizes with RDMA achieve even lower latency.
- RSS
Receive Side Scaling, a technique in the host's network stack for distributing network processing over several CPUs; its latency is higher than RDMA's.
- SMB compression
Shrinks files while they travel over the network using SMB. You can't combine it with SMB Direct over RDMA.
- SMB Direct
Lets SMB 3 run over RDMA network adapters, delivering fast transfers and low latency while using very little processor time.
- VMMQ
A host networking technique distributing a VM's network traffic over several queues; it is slower than RDMA.