KIOXIA innovates a software-enabled flash-drive controller

KIOXIA America (formerly Toshiba Memory America) has announced what it calls Software-Enabled Flash (SEF), a new technology that adds software flexibility, host control and flash-native semantics into a flash-native API and purpose-built controller for flash drives.

Current solid-state disk (SSD) technology is evolved from hard-disk technology and the controllers basically operate much in the same way across the board, whether it’s a SATA drive for your laptop or an NVME over Fabric drive in a data center.

SEF brings programability to the SSD with a software-defined flash controller that offloads low-level functions from the CPU, like error correction and garbage collection, and enables dynamically reconfigurable flash, such as the ability to build a flash storage pool. Data-center operators are the primary target for this SEF technology, but it is also targeted at enterprise customers.

Regular SSD controllers don’t have the best functionality for drive management, and hyperscalers wanted greater programmability of the flash memory for things like storage pooling. However, when controller functionality was removed from the SSD and control was given to the server, it was found that flash operated differently from one vendor to the next and that there was no single way to talk to them all.

SEF adds uniformity to how a server communicates with flash chips regardless of vendor. It only works for SSDs that are SEF compliant, and they are not on the market yet. KIOXIA plans to make the SEF API open source at a later, as-yet undetermined date.

“Our customers have been pushing for the ability to drive operational efficiency in the data center programmatically, and SEF technology will meet this need by placing access and control of flash directly in the hands of hyperscale programmers,” says Eric Ries, senior vice president of the memory storage strategy division at KIOXIA America in a statement.

The closest analogy I can think of is the field programmable gate array processor, which can be reprogrammed as computational needs change. It’s certainly not something you could do with a hard disk because platters and mechanical read/write arms aren’t programmable.

SEF would allow for orchestration of digital storage for cloud applications to drive greater efficiency at scale and create predictable latency even with changing cloud workloads through direct host management.

The SEF is a system-on-chip unit with a microcontroller and flash dies mounted on a printed circuit board with a PCI Express interface. Sub-units handle a variety of management tasks like timing, read tasks with error correction, cell health, and defect management.

It’s all highly technical, so you can check out a Kioxia technical introduction of SEF if you want to make your propeller spin. The bottom line is enterprise flash storage just got a lot more programmable and controllable, and I fully expect competitors like Micron and SK Hynix to come out with their own SEF drives.