---
title: database operations
---

- `POST /db/train`: train zstd compression dictionaries for trainable keyspaces such as `repos` and `events` (plus feature-gated event/index keyspaces). dictionaries are written to disk; a restart is required to apply them. the crawler, firehose, and backfill worker are paused for the duration and restored on completion.
- `POST /db/compact`: trigger a full major compaction of all database keyspaces in parallel. the crawler, firehose, and backfill worker are paused for the duration and restored on completion.