Flash Storage Wear Leveling

Mobile flash storage can't overwrite a page in place — every rewrite means erasing a whole block, and every block has a limited number of program/erase cycles before it dies. This simulator models a small NAND array as a grid of blocks, streams a live mix of hot (constantly overwritten) and cold (write-once) data into it, and runs the flash controller's garbage collector in real time. Toggle static wear leveling on and off to see why relying on garbage collection alone lets cold data sit untouched forever while a shrinking pool of hot blocks races toward failure — and how proactively migrating cold data spreads erase cycles evenly and extends the device's real lifespan.