Operating in production

Maintenance is optional, not required — compaction, WAL pruning and auto-ghosts run unattended. The commands below are levers, not chores.

Introspection

xyzdb> SHOW LOBES
xyzdb> SHOW GHOSTS
xyzdb> SHOW SCAN STATS      # what the router chose

Observability (HTTP)

On the same port, GET / serves a browser operator page and GET /stats returns live metrics as JSON — per-lobe ghost counts, auto-ghost telemetry, compaction and sync health, process memory. Both honor the --auth-token.

$ curl http://127.0.0.1:2505/stats

Maintenance commands

Run from the CLI (the in-language forms are deprecated).

$ xyzdb-cli admin analyze creditos
$ xyzdb-cli admin compact
$ xyzdb-cli admin bulkmode on
$ xyzdb-cli admin migrate --all

Auto-ghosts

A hot query shape (≥ --auto-ghost-min-hits in a 10-min window, average latency ≥ --auto-ghost-min-latency-ms) is promoted to an ephemeral ghost (24 h TTL); a repeatedly useful one becomes promoted (30 d). Set the latency to 1e9 to disable.

Snapshot & lock

Hot snapshots hard-link SSTables under a milliseconds-short lock window; restore is offline. An exclusive flock on the data dir makes a second writer fail fast instead of corrupting it.

$ xyzdb-cli admin snapshot create nightly
$ xyzdb-cli admin snapshot restore --source ./data nightly --target ./restored