A NVDIMM (pronounced "en-vee-dimm") or non-volatile DIMM is a type of persistent random-access memory for computers using widely used DIMM form-factors. Non-volatile memory is memory that retains its contents even when electrical power is removed, for example from an unexpected power loss, system crash, or normal shutdown. Properly used, NVDIMMs can improve application performance and system crash recovery time.[1] They enhance solid-state drive (SSD) endurance and reliability.[2][3]
Many "non-volatile" products use volatile memory during normal operation and dump the contents into non-volatile memory if the power fails, using an on-board backup power source. Volatile memory is faster than non-volatile; it is byte-addressable; and it can be written to arbitrarily, without concerns about wear and device lifespan. However, including a second memory to achieve non-volatility (and the on-board backup power source) increases the product cost compared to volatile memory.
There are many emerging non-volatile memories in development and a few that have been launched including Magnetoresistive RAM (MRAM), Intel's 3D XPoint (discontinued in 2022), Nano-RAM based on carbon nanotubes.[4] The goal of this technology is able to scale cost-effectively scale out so persistent memory could replace DRAM as the main system memory in enterprise systems.[1]