# Configuration Parameters > Source chapter 3.7 for PostgreSQL 11. --- LLMS index: [llms.txt](/en/llms.txt) ---
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In PostgreSQL 11 the following parameters have been changed. #### 3.7.1 Added parameters {#pg11-3-7-1-added-parameters} The following parameters have been added. **Table 16.** Added parameters | Parameter name | Description (context) | Default | | --- | --- | --- | | data_directory_mode | Database cluster protection mode (internal) | 0700 | | enable_parallel_append | Enabled Parallel Append feature (user) | on | | enable_parallel_hash | Enabled Parallel Hash feature (user) | on | | enable_partition_pruning | Enabled partition pruning (user) | on | | enable_partitionwise_aggregate | Enabled Partition-Wise Join feature (user) | off | | enable_partitionwise_join | Enabled Partition-Wise Aggregate feature (user) | off | | jit | Enabled JIT compilation feature (user) | off1 | | jit_above_cost | The Cost to enable JIT compile function (user) 100000 | The Cost to enable JIT compile function (user) 100000 | | jit_debugging_support | Enable debugger at JIT compilation (superuser-backend) | off | | jit_dump_bitcode | Add LLVM bit code (superuser) | off | | jit_expressions | Enable JIT expression (user) | on | | jit_inline_above_cost | The cost to decide whether to make JIT inlining (user) | 500000 | | jit_optimize_above_cost | The cost to decide whether to perform JIT optimization (user) | 500000 | | jit_profiling_support | Enabled perf profiler (superuser-backend) | off | | jit_provider | JIT provider name (postmaster) | llvmjit | | jit_tuple_deforming | Enabled JIT tuple deforming (user) | on | | max_parallel_maintenance_workers Maximum number of parallel workers used in | max_parallel_maintenance_workers Maximum number of parallel workers used in maintenance processing (user) | 2 | | parallel_leader_participation | Change the behavior of the leader process (user) | on | | ssl_passphrase_command | Command to get SSL connection passphrases (sighup) | '' | | ssl_passphrase_command_supports_reload | Whether to use ssl_passphrase_command when reloading (sighup) | off | | vacuum_cleanup_index_scale_factor | The ratio of the number of INSERTs that perform index cleanup (user) | 0.1 | 1 The default value was changed during Beta.

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##### parallel_leader_participation parameter {#pg11-p62-parallel-leader-participation-parameter} When a parallel query is executed, the leader process which coordinates the entire query and the worker processes cooperate with each other. In PostgreSQL 10, the leader process also executed the plan on the Gather and Gather Merge nodes. If this parameter is set to "off", the leader process will not perform the same process as the worker process. The following example searches for table data of 10 million tuples. In both examples, two worker processes are running. In the first example, the portion of Parallel Seq Scan is executed three times with 3,333,333 tuples. In the second example where the parameter parallel_leader_participation is changed to "off", it is executed in 2 loops with 5,000,000 tuples. **Example 77.** Parameter parallel\_leader\_participation \= on ```text postgres=> EXPLAIN ANALYZE SELECT COUNT(*) FROM data1 ; QUERY PLAN ----------------------------------------------------------------------- Finalize Aggregate (cost=107139.46..107139.47 rows=1 width=8) (actual time=8296.629..8296.630 rows=1 loops=1) -> Gather (cost=107139.25..107139.46 rows=2 width=8) (actual time=8295.776..8296.622 rows=3 loops=1) Workers Planned: 2 Workers Launched: 2 -> Partial Aggregate (cost=106139.25..106139.26 rows=1 width=8) (actual time=8276.140..8276.141 rows=1 loops=3) -> Parallel Seq Scan on data1 (cost=0.00..95722.40 rows=4166740 width=0) (actual time=0.096..4168.115 rows=3333333 loops=3) Planning time: 0.026 ms Execution time: 8296.693 ms (8 rows) ```

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**Example 78.** Parameter parallel\_leader\_participation \= off ```text postgres=> SET parallel_leader_participation = off ; SET postgres=> EXPLAIN ANALYZE SELECT COUNT(*) FROM data1 ; QUERY PLAN ----------------------------------------------------------------------- Finalize Aggregate (cost=117556.31..117556.32 rows=1 width=8) (actual time=8448.965..8448.965 rows=1 loops=1) -> Gather (cost=117556.10..117556.30 rows=2 width=8) (actual time=8448. 278..8448.959 rows=2 loops=1) Workers Planned: 2 Workers Launched: 2 -> Partial Aggregate (cost=116556.10..116556.10 rows=1 width=8) (actual time=8441.034..8441.035 rows=1 loops=2) -> Parallel Seq Scan on data1 (cost=0.00..104055.88 rows=5000088 width=0) (actual time=0.214..4423.363 rows=5000000 loops=2) Planning time: 0.026 ms Execution time: 8449.088 ms (8 rows) ``` #### 3.7.2 Changed parameters {#pg11-3-7-2-changed-parameters} The setting range and options were changed for the following configuration parameters. **Table 17.** Changed configuration parameters | log_parser_stats | setting value is | | --- | --- | | log_statement_stats | changed to "on" log_statement_stats | | log_planner_stats | | | log_executor_stats | | | wal_segment_size UNIT of pg_settings catalog changed from 8kB to B | wal_segment_size UNIT of pg_settings catalog changed from 8kB to B | Parameter name Changes ##### log_parser_stats parameter {#pg11-p63-log-parser-stats-parameter} When the value is set to "on", the information output is increased. Additional output information varies depending on the operating system. The example below is for Linux.

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**Example 79.** Parameter log\_parser\_stats \(Linux\) ```text postgres=# SHOW log_parser_stats ; log_parser_stats ------------------ on (1 row) $ tail -11 data/log/postgresql-2018-10-22_092853.log STATEMENT: SHOW log_parser_stats ; LOG: REWRITER STATISTICS DETAIL: ! system usage stats: ! 0.000002 s user, 0.000001 s system, 0.000001 s elapsed ! [0.370726 s user, 0.064474 s system total] ! 12840 kB max resident size ! 0/0 [984/0] filesystem blocks in/out ! 0/0 [1/3208] page faults/reclaims, 0 [0] swaps ! 0 [0] signals rcvd, 0/0 [0/0] messages rcvd/sent ! 0/0 [28/4] voluntary/involuntary context switches ``` #### 3.7.3 Parameters with default values changed {#pg11-3-7-3-parameters-with-default-values-changed} The default values of the following configuration parameters have been changed. **Table 18.** Parameters with default values changed | version | 10.4 | 11.0 | | --- | --- | --- | | server_version_num | 100004 | 110000 | Parameter name PostgreSQL 10 PostgreSQL 11 #### 3.7.4 Obsoleted parameter {#pg11-3-7-4-obsoleted-parameter} The following parameter is obsolete. **Table 19.** Obsoleted parameter | Parameter name | Alternative | | --- | --- | | replacement_sort_tuples | None |

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#### 3.7.5 Authentication parameter change {#pg11-3-7-5-authentication-parameter-change} ##### Instance connect string {#pg11-p65-instance-connect-string} The following parameters have been added to the instance connection string of the Libpq library. **Table 20.** Added parameters | Parameter name | Default | Description | | --- | --- | --- | | replication | false | Specify whether to use replication protocol true: Physical replication database: logical replication | The default value of ssl_compression parameter has been changed to "off". ##### LDAP Authentication parameter {#pg11-p65-ldap-authentication-parameter} The ldapschema parameter has been added for LDAP authentication. Specifying "ldaps" for the parameter uses LDAP over SSL.