Tegile launches Intelliflash tiered all-flash arrays with NVMe

Tegile has launched a new multi-tier flash storage iteration of its Intelliflash HD all-flash platform with serial-attached SCSI solid-state drive (SAS SSD), an NVMe flash tier and encrypted drives. An all-NVMe option is promised for the end of 2017.

The new models add four NVMe slots while all other flash drives are encrypted SAS-connected media. There is also a new version of its controller operating environment, IntelliFlash OS 3.7.

There are two base models, the HD2040 and HD 2080, the former using 4TB SAS flash and the latter 8TB drives. Both can have NVMe flash added in four slots. Both provide block (Fibre Channel and iSCSI) and file (SMB, NFS, CIFS) access.

The HD2040 head unit comprises 24 4TB SAS flash drives for up to 100TB in 2U. The HD2080 uses 8TB drives to give up to 200TB in the same rack space. Both products can have expansion shelves added to take them up to 650TB and 1.3PB respectively.

Paul Silver, Tegile’s vice-president for Europe, the Middle East and Adrica, said: “We’ve taken a very dense platform to another level, provided encryption and made it NVMe-ready for later this year.”

Silver didn’t say to what extent the NVMe slots or even all-NVMe capacity would boost performance, but said: “We’re talking performance [latency] in fractions of a millisecond and that will be in microseconds with NVMe.”

It is not clear whether Tegile can gain the full advantages from NVMe in an architecture without NVMf (NVMe-over-fabrics). Even when all drives are NVMe-capable, unless NVMf is used as a transport, the full potential of NVMe could not be achieved due to the input/output I/O bottleneck at the controller.

Recently, Pure Storage launched an all-NVMe array but said it was happy to gain marginal advantages – 2x or 3x over traditionally connected flash drives – rather than the full potential of NVMe for the time being.

NVMe is a peripheral component interconnect express (PCIe) based standard that potentially allows flash storage to break through the limits imposed by SCSI and its use in the disk-era SAS and serial ATA (SATA) protocols by providing a vast increase in the number of queues and possible queue depth compared to those standards.

But, the controller performs fundamental functions in a storage array, such as protocol handling and physical addressing, as well as storage services such as data reduction, replication and encryption.

For now, that functionality – and the processing overheads it brings – stands in contradiction to the benefits of NVMe, which can operate at full potential when acting as direct-attached storage but which loses its advantages with the bottleneck at the controller in the I/O path.

In a later emailed response, Tegile said, without elaboration: “Just had confirmation that our controllers are ready for NVMe and that the likely bottleneck will be the protocols such as iSCSI.”