For more than 30 years the storage industry has relied on the small computer system interface (SCSI) protocol to communicate between servers and storage and internally to the storage array. But flash storage is pushing the boundaries on SCSI, and vendors are working hard to make a whole host adjustments.
In an article at TechTarget, longtime IT pro Chris Evans explains what’s happening and how vendors are responding. “Flash is orders of magnitude faster than spinning disk and can handle many requests in parallel,” he explains, and “as suppliers push the limits of scalability to drives with tens of terabytes of flash, increasingly SCSI has become the bottleneck to making full use of flash storage.”
And now a new protocol, he notes – non-volatile memory express (NVMe) – is positioned as a replacement for SCSI and promises to fully exploit the benefits of NAND storage.
NVMe is a protocol, not a form factor or type of media, which “reduces the software latency involved in talking to flash, improves hardware interrupt times (processor to device performance) and increases the parallel processing of requests with more and deeper input/output (I/O) queues than SCSI. . . . The result is much higher throughput (IOPS and data volumes) and lower I/O latency.”
Suppliers have started to adopt NVMe, and have used it to build out new and faster storage arrays with NVMe internally deployed, and Evans walks through what some of the vendors – including Pure Storage, E8 Storage and Apeiron Data Systems – are doing to put NVMe to optimal use.
The upshot? “I think in a short time we can expect NVMe to replace SAS and SATA in all performance solutions,” Evans says. “The challenge for customers could be how to implement shared storage that doesn’t use the traditional shared storage array. This means thinking in a more integrated fashion with the whole stack – perhaps along the lines of how hyper-converged infrastructure has developed.”