NVDIMM

An NVDIMM, or non-volatile dual in-line memory module, is a memory module designed to preserve data when power is lost. It combines volatile memory with non-volatile storage so that data held in memory can survive a power outage, enabling faster crash‑consistent recovery than traditional storage.

Common implementations include NVDIMM-N, NVDIMM-F, and NVDIMM-P. NVDIMM-N uses dynamic RAM for fast access plus NAND flash as non-volatile storage and relies on a power-loss protection device, such as a supercapacitor or battery, to transfer data from RAM to flash on power failure. NVDIMM-F is a flash‑only design that provides persistence without a DRAM cache; it offers lower cost but typically higher latency. NVDIMM-P refers to persistent memory modules that use newer non-volatile memory technologies to provide byte-addressable persistence and memory-like performance.

Applications include in-memory databases, high-availability systems, crash-consistent logging, and storage acceleration. They reduce latency and CPU cycles by keeping working data near the processor while ensuring data survives power loss.

Reliability and software: NVDIMMs require support from the server firmware and operating system; software libraries and file systems may expose persistent memory as byte-addressable memory or as block storage, and standards defined by JEDEC govern the interfaces. Overall, NVDIMMs are designed to blur the line between memory and storage, providing persistence with high performance for suitable workloads.