Settings

These are ordinary Postgres GUCs (SET, ALTER DATABASE … SET, or postgresql.conf). Defaults are tuned for good performance, and you usually do not need to change them.

Setting	Default	Notes
`tin.enable_custom_scan`	`on`	When `off`, falls back to generic index scanning (troubleshooting / comparison).
`tin.index_maintenance_mode`	`background`	How index maintenance runs: `background`, `foreground` (in the writing session), or `manual` (no automatic maintenance).
`tin.build_io_concurrency`	`0` (auto)	Caps concurrent disk I/O during `CREATE INDEX` / `REINDEX`. `1` serializes build I/O.
`tin.rss_baseline`	server-derived (MB)	Per-worker RSS estimate used when planning build parallelism.
`tin.maintenance_jobs_per_db`	`0`	How many of its own database’s maintenance jobs a cluster-wide maintenance worker finishes before yielding to another database with queued work. `0` drains the current database first. Set it in `postgresql.conf` or with `ALTER SYSTEM`. A session `SET` is rejected.
`tin.track_page_reuse_stats`	`off`	When `on`, `EXPLAIN ANALYZE` reports distinct vs repeated index page reads.

Debug settings

The tin.debug_* settings are for debugging and testing TIN, not for production use. Each one forces a planning choice the cost model would otherwise make, so that an alternative plan can be measured. They never change query results, and a query shape that would be incorrect is still refused. All of them are session-level (SET) and default to following the cost model.

Setting	Values	Default	Notes
`tin.debug_force_boolean_family`	`auto`, `fused`, `factored`	`auto`	For a query over several TIN indexes, force one combined scan (`fused`) or separate scans joined with boolean operators (`factored`).
`tin.debug_force_topk`	`auto`, `topk`, `exhaustive`	`auto`	For `ORDER BY tin.score(ctid) DESC LIMIT k`, force the bounded top-k scan or an exhaustive scored scan.
`tin.debug_force_multi_index_drive`	`auto`, `sparse`, `stripe`	`auto`	For a query over several TIN indexes, drive from the rarest required term (`sparse`) or evaluate by block range (`stripe`).
`tin.debug_force_conjunction_mode`	`auto`, `generic`, `pushdown`, `noadaptive`	`auto`	Override how an `AND` between a text predicate and another indexed predicate is executed. `noadaptive` only disables the adaptive verifier.
`tin.debug_force_visibility`	`auto`, `streaming`, `sorted`	`auto`	Where a count-only `AND` can check row visibility in streaming or sorted order, force one.
`tin.debug_disable_count_pushdown`	`on`, `off`	`off`	Disable the index-answered `count(*)` path so a plain aggregate over a scan runs instead.
`tin.debug_disable_index_probe`	`on`, `off`	`off`	Disable probing a btree index alongside the text search; mixed predicates fall back to a TIN scan with Postgres filters.
`tin.debug_force_parallel`	`on`, `off`	`off`	Drop serial plans that have a parallel sibling so the parallel plan is chosen, including on tables too small to qualify otherwise.

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