Micron P400m Architecture
XPERT (eXtended Performance and Enhanced Reliability Technology) provides enhanced defect and error management technology. This approach utilizes a combination of hardware based error correction algorithms along with static and dynamic firmware-based wear-leveling algorithms. Micron has implemented data protection and security at every level of the SSDs design, truly dedicating themselves to preserving user data above what many competing solutions offer.
ARM/OR (Adaptive Read Management/Optimized Read) is an adaptive read management technology that dynamically optimizes the NAND as the SSD ages. Over time, natural shifts occur in NAND read locations. This affects the accuracy and endurance of the individual NAND cells. Adaptive management algorithms identify these shifts and adjust read points on-the-fly, aligning them perfectly. This tuning greatly improves the longevity of the NAND.
Micron has taken error correction and avoidance to the next level with RAIN (Redundant of Independent NAND), which calculates and stores parity. This is in essence a RAID 5 implementation at the device level, which provides the ability to recover data in the event of an error or failure. The great thing about RAIN is that it provides data security beyond the standard ECC approach.
The ability to use parity to recreate data, even if ECC cannot correct it, provides an almost 'bulletproof' method of protecting against the increasing amount of errors that comes with NAND as it ages. This transparent process takes place without any degradation of the SSDs performance, but does come at the expense of capacity. This implementation relies upon extra NAND to store the data, but Micron has compensated for this with a generous 70% overprovisioning on the P400m.
ReCAL (Reduced Command Access Latency) enables lower maximum command access/latency through managing internal operations at a granular level. This includes managing wear leveling and other in-house operations to minimize the impact upon service host I/O requests. ReCAL also optimizes the logical-to-physical (L2P) internal data structure by breaking this structure into a series of smaller, more manageable chunks.
[heading Media Customizations
Due to the wearing characteristics of NAND during the course of its life it will fall into three distinct failure regions; early-life, long-term use, and end-of-life. The P400m is pre-cycled at the factory during the manufacturing process. This pre-cycling eliminates the early-life failure region.
DataSAFE protects user data by embedding the LBA metadata along with user data to ensure that the SSD returns the exact data requested.
DataSAFE also protects data as it moves through the SSD. Typical SSD architecture consists of two 'lanes' of traffic through the device. Input and Output operations travel between a series of volatile SRAM, cache and buffer management components. More potential failure points have been introduced as the architecture of SSDs has advanced.
Each of these points in the data traverse can subject the data to corruption and errors. The P400m utilizes expanded data path protection features that ensure the validity of the data is it travels through these possible failure points. User data is effectively "wrapped" in an envelope as it moves through the potential failure points. Enhanced ECC and CRC parity algorithms within the firmware embed RAID-like parity data before each potential failure point in the data traverse, then validates that parity after it passes through the component.
This provides end-to-end data path protection for the Micron P400m.