Allflash

Allflash refers to storage systems and architectures that rely exclusively on flash memory, typically NAND-based solid-state drives, for primary storage rather than traditional spinning hard disk drives. In enterprise contexts, all-flash is used to describe arrays or appliance designs that aim to maximize performance, latency, and throughput by eliminating HDDs from the data path.

All-flash systems leverage flash media and modern interfaces such as PCIe-connected SSDs and NVMe, often with NVMe over Fabrics for networked storage. They commonly implement data reduction techniques like deduplication and compression, as well as advanced wear-leveling, error detection, and redundancy features. Because flash has much lower latency than HDDs, all-flash storage can deliver single-digit millisecond or sub-millisecond latency and tens to hundreds of thousands of IOPS, enabling workloads such as online transaction processing, real-time analytics, large-scale virtualization, and high-performance databases.

However, all-flash storage presents challenges. The cost per gigabyte is higher than HDD-based or hybrid solutions, though prices have fallen substantially. Flash endurance and write amplification require careful wear leveling and over-provisioning, and firmware and controller complexity can affect reliability and performance consistency. Garbage collection and background processes may cause latency spikes if not managed, and capacity planning must account for flash over-provisioning and data protection needs.

Common use cases include databases, virtualization environments, AI/ML workloads, and any workload requiring low latency and high IOPS. All-flash has become a mainstream choice in data centers seeking consistent performance, with many vendors offering purpose-built AFAs (all-flash arrays) and converged/hyper-converged platforms.