# PostgreSQL 10 → 11 GUC diff

> Core configuration parameters added, removed, or changed in boot default between PostgreSQL 10 and 11.
---

> [!NOTE]
> **Fact.** The measured inventory changes from 272 to 292 settings: 21 added, 4 boot-default changes, and 1 removed.

## Added parameters {#added}

| Parameter | Type | Context | Boot default | Category |
| --- | --- | --- | --- | --- |
| [`data_directory_mode`](/parameters/data-directory-mode/) | `integer` | `internal` | `448` | Preset Options |
| [`enable_parallel_append`](/parameters/enable-parallel-append/) | `bool` | `user` | `on` | Query Tuning / Planner Method Configuration |
| [`enable_parallel_hash`](/parameters/enable-parallel-hash/) | `bool` | `user` | `on` | Query Tuning / Planner Method Configuration |
| [`enable_partition_pruning`](/parameters/enable-partition-pruning/) | `bool` | `user` | `on` | Query Tuning / Planner Method Configuration |
| [`enable_partitionwise_aggregate`](/parameters/enable-partitionwise-aggregate/) | `bool` | `user` | `off` | Query Tuning / Planner Method Configuration |
| [`enable_partitionwise_join`](/parameters/enable-partitionwise-join/) | `bool` | `user` | `off` | Query Tuning / Planner Method Configuration |
| [`jit`](/parameters/jit/) | `bool` | `user` | `off` | Query Tuning / Other Planner Options |
| [`jit_above_cost`](/parameters/jit-above-cost/) | `real` | `user` | `100000` | Query Tuning / Planner Cost Constants |
| [`jit_debugging_support`](/parameters/jit-debugging-support/) | `bool` | `superuser-backend` | `off` | Developer Options |
| [`jit_dump_bitcode`](/parameters/jit-dump-bitcode/) | `bool` | `superuser` | `off` | Developer Options |
| [`jit_expressions`](/parameters/jit-expressions/) | `bool` | `user` | `on` | Developer Options |
| [`jit_inline_above_cost`](/parameters/jit-inline-above-cost/) | `real` | `user` | `500000` | Query Tuning / Planner Cost Constants |
| [`jit_optimize_above_cost`](/parameters/jit-optimize-above-cost/) | `real` | `user` | `500000` | Query Tuning / Planner Cost Constants |
| [`jit_profiling_support`](/parameters/jit-profiling-support/) | `bool` | `superuser-backend` | `off` | Developer Options |
| [`jit_provider`](/parameters/jit-provider/) | `string` | `postmaster` | `llvmjit` | Client Connection Defaults / Shared Library Preloading |
| [`jit_tuple_deforming`](/parameters/jit-tuple-deforming/) | `bool` | `user` | `on` | Developer Options |
| [`max_parallel_maintenance_workers`](/parameters/max-parallel-maintenance-workers/) | `integer` | `user` | `2` | Resource Usage / Asynchronous Behavior |
| [`parallel_leader_participation`](/parameters/parallel-leader-participation/) | `bool` | `user` | `on` | Resource Usage / Asynchronous Behavior |
| [`ssl_passphrase_command`](/parameters/ssl-passphrase-command/) | `string` | `sighup` | `""` (empty string) | Connections and Authentication / SSL |
| [`ssl_passphrase_command_supports_reload`](/parameters/ssl-passphrase-command-supports-reload/) | `bool` | `sighup` | `off` | Connections and Authentication / SSL |
| [`vacuum_cleanup_index_scale_factor`](/parameters/vacuum-cleanup-index-scale-factor/) | `real` | `user` | `0.1` | Client Connection Defaults / Statement Behavior |
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## Boot-default changes {#default-changes}

| Parameter | PG10 | PG11 | Category |
| --- | --- | --- | --- |
| [`server_version`](/parameters/server-version/) | `10.23 (Debian 10.23-1.pgdg110+1)` | `11.22 (Debian 11.22-1.pgdg120+1)` | Preset Options |
| [`server_version_num`](/parameters/server-version-num/) | `100023` | `110022` | Preset Options |
| [`track_activity_query_size`](/parameters/track-activity-query-size/) | `1024` | `1024 B` (1 KiB) | Resource Usage / Memory |
| [`wal_segment_size`](/parameters/wal-segment-size/) | `2048 8kB` (16 MiB (2048 × 8kB)) | `16777216 B` (16 MiB) | Preset Options |
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## Removed parameters {#removed}

| Parameter | Last type | Context | Last boot default | Category |
| --- | --- | --- | --- | --- |
| [`replacement_sort_tuples`](/parameters/replacement-sort-tuples/) | `integer` | `user` | `150000` | Resource Usage / Memory |
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## Method {#method}

The three lists compare the pinned PG10 and PG11 `pg_settings` snapshots directly. A default change is a change in the `boot_val` plus `unit` pair; `setting` is excluded so an `initdb`-generated value is not mistaken for the compiled boot default.

- [Machine-readable diff data](/data/diffs.json)
- [Complete GUC JSONL](/data/guc.jsonl)