The trace runs on the Python engine on the server; the browser only renders the streamed grid snapshots.
New to SSDs? This page shows, live, what happens inside a solid-state drive as a
workload writes to it — how data lands in flash blocks, how stale data piles up, and how garbage collection and
wear unfold over time. Switch to ZNS mode to see zoned namespaces instead.
👉 For a plain-English, beginner-friendly explanation of every concept (blocks, pages, WAF,
garbage collection, wear leveling, ZNS…), read the Learn SSD blog. Each idea used on this
page has its own illustrated post.
Each small square is one flash block, grouped by Channel → Chip → Die → Plane
(the parallel geometry chosen above). Color follows the advance-simulator code:
the green channel encodes the invalid (stale) page ratio — near-black = mostly valid,
bright green = mostly invalid.
free (erased)
✓ fully valid
mostly valid
mostly invalid
✗ fully invalid
Each box is one zone (a group of blocks written strictly sequentially). The bar shows the zone's pages:
valid (live)
stale (invalidated)
unwritten (below write pointer)
— border: EMPTYOPENFULL.
● hot / ● cold mark the open streams; the number is the zone's reset count.
Live metrics
Computed from each streamed snapshot — they redraw at your chosen update frequency, same as the grid.