postgresql.conf.example

data_directory = '/var/lib/postgresql/data'
hba_file = '/etc/postgresql/pg_hba.conf'
#ident_file = '/etc/postgresql/pg_ident.conf'
external_pid_file = '/var/run/postgresql/main.pid'

#------------------------------------------------------------------------------
# CONNECTIONS AND AUTHENTICATION
#------------------------------------------------------------------------------

# - Connection Settings -

listen_addresses = '*'
port = 5432
max_connections = 100
superuser_reserved_connections = 5
unix_socket_directories = '/var/run/postgresql'
#unix_socket_group = ''
#unix_socket_permissions = 0777     # begin with 0 to use octal notation
#bonjour = off              # advertise server via Bonjour
#bonjour_name = ''          # defaults to the computer name

# - Security and Authentication -

#authentication_timeout = 1min      # 1s-600s
ssl = on
#ssl_ciphers = 'HIGH:MEDIUM:+3DES:!aNULL' # allowed SSL ciphers
#ssl_prefer_server_ciphers = on
#ssl_ecdh_curve = 'prime256v1'
#ssl_dh_params_file = ''
ssl_cert_file = '/etc/ssl/certs/ssl-cert-snakeoil.pem'
ssl_key_file = '/etc/ssl/private/ssl-cert-snakeoil.key'
#ssl_ca_file = ''
#ssl_crl_file = ''
#password_encryption = md5      # md5 or scram-sha-256
#db_user_namespace = off
#row_security = on

# - TCP Keepalives -
# see "man 7 tcp" for details
#tcp_keepalives_idle = 0        # TCP_KEEPIDLE, in seconds; 0 selects the system default
#tcp_keepalives_interval = 0        # TCP_KEEPINTVL, in seconds; 0 selects the system default
#tcp_keepalives_count = 0       # TCP_KEEPCNT;  0 selects the system default

#------------------------------------------------------------------------------
# RESOURCE USAGE (except WAL)
#------------------------------------------------------------------------------

# - Memory -

shared_buffers = 128MB          # min 128kB
#huge_pages = try           # on, off, or try
#temp_buffers = 8MB         # min 800kB
#max_prepared_transactions = 0      # zero disables the feature
# Caution: it is not advisable to set max_prepared_transactions nonzero unless
# you actively intend to use prepared transactions.
#work_mem = 4MB             # min 64kB
#maintenance_work_mem = 64MB        # min 1MB
#replacement_sort_tuples = 150000   # limits use of replacement selection sort
#autovacuum_work_mem = -1       # min 1MB, or -1 to use maintenance_work_mem
#max_stack_depth = 2MB          # min 100kB
dynamic_shared_memory_type = posix

# - Disk -

#temp_file_limit = -1           # limits per-process temp file space in kB, or -1 for no limit

# - Kernel Resource Usage -

#max_files_per_process = 1000       # min 25
#shared_preload_libraries = ''

# - Cost-Based Vacuum Delay -

#vacuum_cost_delay = 0          # 0-100 milliseconds
#vacuum_cost_page_hit = 1       # 0-10000 credits
#vacuum_cost_page_miss = 10     # 0-10000 credits
#vacuum_cost_page_dirty = 20        # 0-10000 credits
#vacuum_cost_limit = 200        # 1-10000 credits

# - Background Writer -

#bgwriter_delay = 200ms         # 10-10000ms between rounds
#bgwriter_lru_maxpages = 100        # 0-1000 max buffers written/round
#bgwriter_lru_multiplier = 2.0      # 0-10.0 multiplier on buffers scanned/round
#bgwriter_flush_after = 512kB       # measured in pages, 0 disables

# - Asynchronous Behavior -

#effective_io_concurrency = 1       # 1-1000; 0 disables prefetching
#max_worker_processes = 8       # (change requires restart)
#max_parallel_workers_per_gather = 2    # taken from max_parallel_workers
#max_parallel_workers = 8       # maximum number of max_worker_processes that can be used in parallel queries
#old_snapshot_threshold = -1        # 1min-60d; -1 disables; 0 is immediate
#backend_flush_after = 0        # measured in pages, 0 disables

#------------------------------------------------------------------------------
# WRITE AHEAD LOG
#------------------------------------------------------------------------------

# set wal_level to its default (replica) for all nodes of the cluster
wal_level = replica  # minimal, replica, or logical

# - Settings for master -

#fsync = on             # flush data to disk for crash safety (turning this off can cause unrecoverable data corruption)
#synchronous_commit = on        # synchronization level; # off, local, remote_write, remote_apply, or on
#wal_sync_method = fsync        # the default is the first option
                    # supported by the operating system:
                    #   open_datasync
                    #   fdatasync (default on Linux)
                    #   fsync
                    #   fsync_writethrough
                    #   open_sync
#full_page_writes = on          # recover from partial page writes
#wal_compression = off          # enable compression of full-page writes
#wal_log_hints = off            # also do full page writes of non-critical updates
#wal_buffers = -1           # min 32kB, -1 sets based on shared_buffers
#wal_writer_delay = 200ms       # 1-10000 milliseconds
#wal_writer_flush_after = 1MB       # measured in pages, 0 disables

#commit_delay = 0           # range 0-100000, in microseconds
#commit_siblings = 5            # range 1-1000

# - Archiving for master -

archive_mode = on       # enables archiving; off, on, or always
archive_command = 'cp %p /var/backups/postgresql/archive/%f' # command to use to archive a logfile segment
                # placeholders: %p = path of file to archive
                #               %f = file name only
                # e.g. 'test ! -f /mnt/server/archivedir/%f && cp %p /mnt/server/archivedir/%f'
archive_timeout = 0     # force a logfile segment switch after this number of seconds; 0 disables

# - Checkpoints -

#checkpoint_timeout = 5min      # range 30s-1d
#max_wal_size = 1GB
#min_wal_size = 80MB
#checkpoint_completion_target = 0.5 # checkpoint target duration, 0.0 - 1.0
#checkpoint_flush_after = 256kB     # measured in pages, 0 disables
#checkpoint_warning = 30s       # 0 disables

#------------------------------------------------------------------------------
# REPLICATION
#------------------------------------------------------------------------------

# - Sending Server(s) -

# Set these on the master and on any standby that will send replication data.

max_wal_senders = 6     # max number of walsender processes
wal_keep_segments = 32  # in logfile segments, 16MB each; 0 disables
wal_sender_timeout = 60s    # in milliseconds; 0 disables

#max_replication_slots = 10 # max number of replication slots
#track_commit_timestamp = off   # collect timestamp of transaction commit

# - Master Server -

# These settings are ignored on a standby server.

#synchronous_standby_names = '' # standby servers that provide sync rep method to choose sync standbys, 
                # number of sync standbys, and comma-separated list of application_name from standby(s); '*' = all
#vacuum_defer_cleanup_age = 0   # number of xacts by which cleanup is delayed

# - Standby Servers -

# These settings are ignored on a master server.

hot_standby = on            # "off" disallows queries during recovery
#max_standby_archive_delay = 30s    # max delay before canceling queries
                    # when reading WAL from archive; -1 allows indefinite delay
#max_standby_streaming_delay = 30s  # max delay before canceling queries
                    # when reading streaming WAL;  -1 allows indefinite delay
#wal_receiver_status_interval = 10s # send replies at least this often; 0 disables
#hot_standby_feedback = off     # send info from standby to prevent query conflicts
#wal_receiver_timeout = 60s     # time that receiver waits for communication from master; in milliseconds; 0 disables
#wal_retrieve_retry_interval = 5s   # time to wait before retrying to retrieve WAL after a failed attempt

# - Subscribers -

# These settings are ignored on a publisher.

#max_logical_replication_workers = 4    # taken from max_worker_processes
#max_sync_workers_per_subscription = 2  # taken from max_logical_replication_workers

#------------------------------------------------------------------------------
# QUERY TUNING
#------------------------------------------------------------------------------

# - Planner Method Configuration -

#enable_bitmapscan = on
#enable_hashagg = on
#enable_hashjoin = on
#enable_indexscan = on
#enable_indexonlyscan = on
#enable_material = on
#enable_mergejoin = on
#enable_nestloop = on
#enable_seqscan = on
#enable_sort = on
#enable_tidscan = on

# - Planner Cost Constants -

#seq_page_cost = 1.0            # measured on an arbitrary scale
#random_page_cost = 4.0         # same scale as above
#cpu_tuple_cost = 0.01          # same scale as above
#cpu_index_tuple_cost = 0.005       # same scale as above
#cpu_operator_cost = 0.0025     # same scale as above
#parallel_tuple_cost = 0.1      # same scale as above
#parallel_setup_cost = 1000.0   # same scale as above
#min_parallel_table_scan_size = 8MB
#min_parallel_index_scan_size = 512kB
#effective_cache_size = 4GB

# - Genetic Query Optimizer -

#geqo = on
#geqo_threshold = 12
#geqo_effort = 5            # range 1-10
#geqo_pool_size = 0         # selects default based on effort
#geqo_generations = 0           # selects default based on effort
#geqo_selection_bias = 2.0      # range 1.5-2.0
#geqo_seed = 0.0            # range 0.0-1.0

# - Other Planner Options -

#default_statistics_target = 100    # range 1-10000
#constraint_exclusion = partition   # on, off, or partition
#cursor_tuple_fraction = 0.1        # range 0.0-1.0
#from_collapse_limit = 8
#join_collapse_limit = 8        # 1 disables collapsing of explicit JOIN clauses
#force_parallel_mode = off

#------------------------------------------------------------------------------
# ERROR REPORTING AND LOGGING
#------------------------------------------------------------------------------

# - Where to Log -

log_destination = 'stderr'
logging_collector = off

# - When to Log -

#client_min_messages = notice
#log_min_messages = warning
#log_min_error_statement = error

#log_min_duration_statement = -1    # -1 is disabled, 0 logs all statements
                    # and their durations, > 0 logs only statements running at least this number of milliseconds

# - What to Log -

#debug_print_parse = off
#debug_print_rewritten = off
#debug_print_plan = off
#debug_pretty_print = on
#log_checkpoints = off
#log_connections = off
#log_disconnections = off
#log_duration = off
#log_error_verbosity = default      # terse, default, or verbose messages
#log_hostname = off
log_line_prefix = '%m [%p] %q%u@%d '
#log_lock_waits = off           # log lock waits >= deadlock_timeout
#log_statement = 'none'         # none, ddl, mod, all
#log_replication_commands = off
#log_temp_files = -1            # log temporary files equal or larger  than the specified size in kilobytes; -1 disables, 0 logs all temp files
log_timezone = 'UTC'

#------------------------------------------------------------------------------
# RUNTIME STATISTICS
#------------------------------------------------------------------------------

# - Query/Index Statistics Collector -

#track_activities = on
#track_counts = on
#track_io_timing = off
#track_functions = none         # none, pl, all
#track_activity_query_size = 1024   # (change requires restart)
#stats_temp_directory = '/var/run/postgresql/main.pg_stat_tmp'

# - Statistics Monitoring -

#log_parser_stats = off
#log_planner_stats = off
#log_executor_stats = off
#log_statement_stats = off

#------------------------------------------------------------------------------
# AUTOVACUUM PARAMETERS
#------------------------------------------------------------------------------

#autovacuum = on            # Enable autovacuum subprocess?  'on' requires track_counts to also be on.
#log_autovacuum_min_duration = -1   # -1 disables, 0 logs all actions and their durations, > 0 logs only
                    # actions running at least this number of milliseconds.
#autovacuum_max_workers = 3     # max number of autovacuum subprocesses
#autovacuum_naptime = 1min      # time between autovacuum runs
#autovacuum_vacuum_threshold = 50   # min number of row updates before vacuum
#autovacuum_analyze_threshold = 50  # min number of row updates before analyze
#autovacuum_vacuum_scale_factor = 0.2   # fraction of table size before vacuum
#autovacuum_analyze_scale_factor = 0.1  # fraction of table size before analyze
#autovacuum_freeze_max_age = 200000000  # maximum XID age before forced vacuum
#autovacuum_multixact_freeze_max_age = 400000000    # maximum multixact age before forced vacuum
#autovacuum_vacuum_cost_delay = 20ms    # default vacuum cost delay for autovacuum, in milliseconds;
                    # -1 means use vacuum_cost_delay
#autovacuum_vacuum_cost_limit = -1  # default vacuum cost limit for autovacuum, -1 means use vacuum_cost_limit

#------------------------------------------------------------------------------
# CLIENT CONNECTION DEFAULTS
#------------------------------------------------------------------------------

# - Statement Behavior -

#search_path = '"$user", public'    # schema names
#default_tablespace = ''        # a tablespace name, '' uses the default
#temp_tablespaces = ''          # a list of tablespace names, '' uses only default tablespace
#check_function_bodies = on
#default_transaction_isolation = 'read committed'
#default_transaction_read_only = off
#default_transaction_deferrable = off
#session_replication_role = 'origin'
#statement_timeout = 0          # in milliseconds, 0 is disabled
#lock_timeout = 0           # in milliseconds, 0 is disabled
#idle_in_transaction_session_timeout = 0    # in milliseconds, 0 is disabled
#vacuum_freeze_min_age = 50000000
#vacuum_freeze_table_age = 150000000
#vacuum_multixact_freeze_min_age = 5000000
#vacuum_multixact_freeze_table_age = 150000000
#bytea_output = 'hex'           # hex, escape
#xmlbinary = 'base64'
#xmloption = 'content'
#gin_fuzzy_search_limit = 0
#gin_pending_list_limit = 4MB

# - Locale and Formatting -

datestyle = 'iso, mdy'
#intervalstyle = 'postgres'
timezone = 'UTC'
#timezone_abbreviations = 'Default'     # Select the set of available time zone abbreviations.
#extra_float_digits = 0         # min -15, max 3
#client_encoding = sql_ascii        # actually, defaults to database encoding

# These settings are initialized by initdb, but they can be changed.
lc_messages = 'en_US.UTF-8'         # locale for system error message strings
lc_monetary = 'en_US.UTF-8'         # locale for monetary formatting
lc_numeric = 'en_US.UTF-8'          # locale for number formatting
lc_time = 'en_US.UTF-8'             # locale for time formatting

# default configuration for text search
default_text_search_config = 'pg_catalog.english'

#------------------------------------------------------------------------------
# LOCK MANAGEMENT
#------------------------------------------------------------------------------

#deadlock_timeout = 1s
#max_locks_per_transaction = 64     # min 10
#max_pred_locks_per_transaction = 64    # min 10
#max_pred_locks_per_relation = -2   # negative values mean (max_pred_locks_per_transaction  / -max_pred_locks_per_relation) - 1
#max_pred_locks_per_page = 2            # min 0

#------------------------------------------------------------------------------
# ERROR HANDLING
#------------------------------------------------------------------------------

#exit_on_error = off            # terminate session on any error?
#restart_after_crash = on       # reinitialize after backend crash?