The InfiniBand Trade Association recently had the opportunity to speak on RDMA technology at the 2015 Storage Developer Conference. For the first time, SDC15 introduced Pre-conference Primer Sessions covering topics such as Persistent Memory, Cloud and Interop and Data Center Infrastructure. Intel’s David Cohen, System Architect and Brian Hausauer, Hardware Architect spoke on behalf of IBTA in a pre-conference session and discussed “Nonvolatile Memory (NVM), four trends in the modern data center and implications for the design of next generation distributed storage systems.”
Below is a high level overview of their presentation:
The modern data center continues to transform as applications and uses change and develop. Most recently, we have seen users abandon traditional storage architectures for the cloud. Cloud storage is founded on data-center-wide connectivity and scale-out storage, which delivers significant increases in capacity and performance, enabling application deployment anytime, anywhere. Additionally, job scheduling and system balance capabilities are boosting overall efficiency and optimizing a variety of essential data center functions.
Trends in the modern data center are appearing as cloud architecture takes hold. First, the performance of network bandwidth and storage media is growing rapidly. Furthermore, operating system vendors (OSV) are optimizing the code path of their network and storage stacks. All of these speed and efficiency gains to network bandwidth and storage are occurring while single processor/core performance remains relatively flat.
Data comes in a variety of flavors, some of which is accessed frequently for application I/O requests and others that are rarely retrieved. To enable higher performance and resource efficiency, cloud storage uses a tiering model to access data based on what is accessed most often. Data that is regularly accessed is stored on expensive, high performance media (solid-state drives). Data that is hardly or never retrieved is relegated to less expensive media with the lowest $/GB (rotational drives). This model follows a Hot, Warm and Cold data pattern and allows you faster access to what you use the most.
The growth of high performance storage media is driving the need for innovation in the network, primarily addressing application latency. This is where Remote Direct Memory Access (RDMA) comes into play. RDMA is an advanced, reliable transport protocol that enhances the efficiency of workload processing. Essentially, it increases data center application performance by offloading the movement of data from the CPU. This lowers overhead and allows the CPU to focus its processing power on running applications, which in turn reduces latency.
Demand for cloud storage is increasing and the need for RDMA and high performance storage networking grows as well. With this in mind, the InfiniBand Trade Association is continuing its work developing the RDMA architecture for InfiniBand and Ethernet (via RDMA over Converged Ethernet or RoCE) topologies.