3.2.12 Maximum Performance and Low Latencies
As flash and non-volatile memory technologies continue to evolve rapidly, with the emergence of new flash form factors, and new flash interfaces, these technologies have the potential to further reduce storage latencies by an order of magnitude. In fact, read and write latencies will soon become much faster than doing a network hop. As a result, the only way to really leverage the enormous performance gains of these new technologies is to eliminate that network hop and bring the data much closer to the compute—onto the same server.
VMware continues the performance improvement of vSAN by expanding the support of new types of hardware devices and interfaces. For instance:
• ULLtraDIMM – ULLtraDIMM SSDs connect flash storage to the memory channel via DIMM slots, achieving very low (<5us) write latency. UltraDIMM provides even greater density and performance. For example, it allows for a 12-TB all-flash vSAN host in a thin blade form factor, as well as three times improvement in latency compared to external arrays.
• NVMe – Non-volatile Memory Express (NVMe) is a new communications interface developed especially for SSDs. NVMe provides greater parallelism for both hardware and software, and as a result, enables performance improvements. Leveraging NVMe in a vSAN all flash deployment resulted in 3.2M IOPS measured on a 32-node cluster ~100K IOPS/host.