The ANALYZE command can be used to collect statistics about the contents of the tables in the CrateDB cluster.

The generated statistics can be viewed in the pg_catalog.pg_stats table.

The query optimizer uses some of those statistics to generate better execution plans.

The statistics are also periodically updated. How often can be configured with the stats.service.interval setting.

I/O throughput during collection of statistics can be throttled with the stats.service.max_bytes_per_sec setting. Changes to this setting can be made and take effect while an analysis is in progress, thus it’s possible to adjust optimal value for a concrete setup by trying different values while ANALYZE is running.