LSM-Tree Storage Engine a real engine, instrumented live — persists to IndexedDB; refresh = crash recovery

Controls

Every button here calls the real engine. Each call records the steps it actually took — read them in the trace below the tree.

Console


        

Workload

Seeded and deterministic — the same seed replays the same operation stream.

Knobs

Change these under load and watch the amplification tiles move — no setting wins on all three.

Tree

WAL
0 records
durable before any write is acknowledged
memtable
skiplist, sorted in memory → flushes when full
levels L0 runs overlap (each is one flushed memtable); L1+ are sorted and non-overlapping. Click any run to inspect its bytes.

Operation trace — run an operation to see its steps

Emitted by the engine as it executes, one line per step it actually performed. Nothing here is scripted.

    Metrics live

    write amp
    read amp
    space amp
    bloom skips

    per-level size

    log