NAND Flash

2 articles

Tech 15 Sep 2026 5 min read

SSD Write Cache and Sustained Transfer Speed

An SSD can copy the first part of a large file at high speed, then settle at a much lower rate even though nothing else appears to have changed. That drop can be normal. Many consumer SSDs use part of their NAND as a fast write cache, allowing short bursts to finish before the drive has to sustain writes in its denser storage mode. This behavior makes a single peak transfer number a poor description of every write workload. Cache size, free space, NAND type, controller policy, temperature, and the amount of data already waiting inside the drive can all affect the speed seen during a long transfer.

SSD Storage

Tech 14 Sep 2026 7 min read

Flash Wear Leveling Spreads Writes Across NAND Cells

A file can keep the same name and logical location while its bytes move through many different physical locations inside an SSD, phone, memory card, or USB drive. That movement is not a side effect of a messy file system. It is a core part of managing NAND flash. Flash memory has a finite program-and-erase endurance. Rewriting the same physical area continuously would age that area much faster than the rest of the device. Controllers avoid that pattern by spreading writes across available flash. This process is called wear leveling.

Storage NAND Flash