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NAND Flash and the FTL

Write pages, watch the FTL remap, run GC, and measure write amplification live

NAND flash: 8 blocks × 8 pagesblock 0E:0block 1E:0block 2E:0block 3E:0block 4E:0block 5E:0block 6E:0block 7E:0host writes: 0NAND writes: 0erases: 0WAF: 0.00legend:freevalidinvalidmapped LBAs: 0free pages: 64 / 64
interactiveBeginner

Press "write sequential" to write the next logical block, or "write random" to write a random block. Watch how every write lands in a fresh page and old locations turn red (invalid). Run "GC" to reclaim invalid pages by copying surviving data and erasing the source block.

Press "write 4 KiB" to start. Watch the FTL map LBAs to fresh pages.

W = seq write · R = rand write · G = GC · T = TRIM · X = reset

Tap buttons to drive the SSD

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