gin_pending_list_limit
Fact — official short description: “Sets the maximum size of the pending list for GIN index.”
Identity
Lifecycle
| Fact | Value |
|---|---|
| First observed | PG9.5 |
| Present in | PG9.5–19 Beta 3 |
| Removed in | No |
| Introduction commit | c291503b1c82 — Rename pending_list_cleanup_size to gin_pending_list_limit. |
| Commit date | 2014-11-13 |
| Discussion | — |
Default history
| Versions | Raw boot_val |
Unit | Human value |
|---|---|---|---|
| PG9.5–19 Beta 3 | 4096 |
kB |
4 MiB |
How it works
gin_pending_list_limit sets the maximum size of the pending list for GIN index. With a GIN index’s fastupdate enabled, crossing this limit triggers bulk migration from the pending list into the main index; per-index storage parameters can override it.
gin_pending_list_limit is a USER-context setting. An authorized role can change it for a session, while ALTER ROLE or ALTER DATABASE can establish a default for future sessions.
GIN behavior also depends on per-index storage parameters, work or maintenance memory, autovacuum, and the shape of indexed values and predicates.
Tuning advice
Advice. These are workload-specific starting points and must be validated with measurements.
| Workload | Guidance |
|---|---|
| OLTP | Change gin_pending_list_limit only after measuring the affected GIN maintenance or search path. Prefer an index-level override when one index, rather than the whole cluster, is exceptional. |
| OLAP | For batch loads or broad searches, test gin_pending_list_limit against ingestion latency, cleanup spikes, result completeness, and maintenance windows. |
| Small nodes | Do not raise gin_pending_list_limit merely because the default is reached; bound memory and I/O bursts, and keep exact-query semantics unless approximation is explicitly acceptable. |
Pigsty
Values use the fixed 8-vCPU, 32-GiB, 100-GiB SSD fixture and render the current Pigsty templates for PG19 Beta 3; this does not assert current Pigsty support for that historical or beta release.
| Template | Effective value | Versus upstream boot | Source expression |
|---|---|---|---|
| OLTP | Unmodified | — | — |
| OLAP | Unmodified | — | — |
| CRIT | Unmodified | — | — |
| TINY | Unmodified | — | — |
Advice — pending human review. Fact from the current Pigsty template projection: OLTP: PG9.5–19 Beta 3 unmodified; OLAP: PG9.5–19 Beta 3 unmodified; CRIT: PG9.5–19 Beta 3 unmodified; TINY: PG9.5–19 Beta 3 unmodified. No Pigsty-specific rationale is inferred from an absent override.
Common pitfalls
- Changing gin_pending_list_limit in one session and assuming role defaults, database defaults, or other pooled sessions changed with it.
- Applying a cluster-wide GIN value to fix one exceptional index instead of using its storage parameters.
- Ignoring cleanup latency, I/O bursts, autovacuum interaction, or result completeness while tuning.
- Changing gin_pending_list_limit globally without a rollback plan and a client or operational compatibility test.
Related parameters
gin_fuzzy_search_limit · maintenance_work_mem · work_mem · vacuum_cleanup_index_scale_factor · autovacuum_work_mem
References
- PostgreSQL 19 Beta 3 — gin_pending_list_limit
- PostgreSQL 19 release notes
- Machine-readable GUC export