leungchopan - Fotolia
NVMe flash storage provider Excelero has added storage networking options that include Ethernet and Fibre Channel, plus erasure coding as a data protection method.
In a set of upgrades that come under the umbrella NVMesh2, Excelero has added the ability to connect NVMe storage instances using Ethernet/TCP-IP and Fibre Channel. This broadens connectivity options from RDMA (remote direct memory access), which was all that was available previously, and is known as MeshConnect.
According to Excelero CTO Yaniv Romem, there is a small performance hit when using other than RDMA, but he believes customers will be willing to swap flexibility of deployment options for a small cut in performance levels.
Romem said that with a baseline disk latency of about 100µs, users that deploy RDMA can expect total latency of about 105µs. With TCP-IP or Fibre Channel connectivity, that stretches to 180µs.
“Don’t forget that most flash arrays only talk about sub-millisecond latency, and this is a lot quicker than that,” he said.
An advantage cited by Excelero is that these options allow customers to move to NVMesh and use their existing networking hardware. RDMA needs specialised network interface cards (NICs).
Another upgrade announced is the addition of erasure coding as a data protection option between Excelero hardware instances, known as MeshProtect. Previously, combinations of RAID that used striping and mirroring of data were possible, but now a parity-based erasure coding is also possible.
This sees parity data that can help rebuild lost drives or sectors distributed across all other drives. This makes it more space-efficient in terms of capacity utilisation than RAID levels that use an entire drive for parity data.
According to Romem, use of erasure coding with NVMesh will allow up to 90% drive utilisation. Mirrored RAID sets would allow for only 50% by comparison.
Read more on NVMe flash storage
- NVMe can unleash flash by doing away with the built-for-disk SCSI protocol. But so far there is no consensus between suppliers about how to build products around NVMe.
- NVMe can unlock the true potential of flash, but storage controllers put a bottleneck back in the I/O path. We look at how suppliers are trying to solve the problem.
NVMesh is aimed at webscale and cloud customers, for data analysis, transactional operations, machine learning, video processing and high-performance computing workloads. Customers include NASA, Technicolor and General Electric.
RDMA is a method that allows data to be moved between the main memory across different devices. TCP-IP on Ethernet and Fibre Channel are more conventional (storage) networking protocols.
NVMe is a PCIe-based standard for card format drives that allows solid state storage to boost its full potential hugely by increasing drive connectivity performance, with large numbers of queues and vastly increased queue depth in the input/output (I/O) path.
NVMesh2 will also provide its own GUI-based performance monitoring, in which capacity and performance – down to volume or client level – can be tracked, in a feature called MeshInspect.
Excelero’s NVMesh2 upgrades are currently in beta and will be available in early 2019.