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# -----------------------------
# PostgreSQL configuration file
# -----------------------------
#
# This file consists of lines of the form:
#
# name = value
#
# (The "=" is optional.) Whitespace may be used. Comments are introduced with
# "#" anywhere on a line. The complete list of parameter names and allowed
# values can be found in the PostgreSQL documentation.
#
# The commented-out settings shown in this file represent the default values.
# Re-commenting a setting is NOT sufficient to revert it to the default value;
# you need to reload the server.
#
# This file is read on server startup and when the server receives a SIGHUP
# signal. If you edit the file on a running system, you have to SIGHUP the
# server for the changes to take effect, run "pg_ctl reload", or execute
# "SELECT pg_reload_conf()". Some parameters, which are marked below,
# require a server shutdown and restart to take effect.
#
# Any parameter can also be given as a command-line option to the server, e.g.,
# "postgres -c log_connections=on". Some parameters can be changed at run time
# with the "SET" SQL command.
#
# Memory units: kB = kilobytes Time units: ms = milliseconds
# MB = megabytes s = seconds
# GB = gigabytes min = minutes
# TB = terabytes h = hours
# d = days
#------------------------------------------------------------------------------
# FILE LOCATIONS
#------------------------------------------------------------------------------
# The default values of these variables are driven from the -D command-line
# option or PGDATA environment variable, represented here as ConfigDir.
#data_directory = 'ConfigDir' # use data in another directory
# (change requires restart)
#hba_file = 'ConfigDir/pg_hba.conf' # host-based authentication file
# (change requires restart)
#ident_file = 'ConfigDir/pg_ident.conf' # ident configuration file
# (change requires restart)
# If external_pid_file is not explicitly set, no extra PID file is written.
#external_pid_file = '' # write an extra PID file
# (change requires restart)
#------------------------------------------------------------------------------
# CONNECTIONS AND AUTHENTICATION
#------------------------------------------------------------------------------
# - Connection Settings -
listen_addresses = '0.0.0.0' # what IP address(es) to listen on;
# comma-separated list of addresses;
# defaults to 'localhost'; use '*' for all
# (change requires restart)
# 根据业务需求设定监听
port = 1921 # (change requires restart)
# 建议不要大于 200 * 四分之一物理内存(GB)， 例如四分之一物理内存为16G，则建议不要超过3200\.
# (假设一个连接耗费5MB，实际上syscache很大时，可能更多)
# [《PostgreSQL relcache在长连接应用中的内存霸占"坑"》](201607/20160709_01.md)
max_connections = 2000 # (change requires restart)
superuser_reserved_connections = 13 # (change requires restart)
# $PGDATA, /tmp中 创建unix socket监听
unix_socket_directories = '/tmp,.' # comma-separated list of directories
# (change requires restart)
#unix_socket_group = '' # (change requires restart)
# 除了OWNER和超级用户，其他用户无法从/tmp unix socket连接该实例
unix_socket_permissions = 0700 # begin with 0 to use octal notation
# (change requires restart)
#bonjour = off # advertise server via Bonjour
# (change requires restart)
#bonjour_name = '' # defaults to the computer name
# (change requires restart)
# - Security and Authentication -
#authentication_timeout = 1min # 1s-600s
#ssl = off
#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 = 'server.crt'
#ssl_key_file = 'server.key'
#ssl_ca_file = ''
#ssl_crl_file = ''
# md5 or scram-sha-256 # 如果MD5会泄露，建议使用scram-sha-256，但是相互不兼容，请注意。
# [《PostgreSQL 10.0 preview 安全增强 - SASL认证方法 之 scram-sha-256 安全认证机制》](201703/20170309_01.md)
password_encryption = md5
#db_user_namespace = off
#row_security = on
# GSSAPI using Kerberos
#krb_server_keyfile = ''
#krb_caseins_users = off
# - TCP Keepalives -
# see "man 7 tcp" for details
tcp_keepalives_idle = 60 # TCP_KEEPIDLE, in seconds;
# 0 selects the system default
tcp_keepalives_interval = 10 # TCP_KEEPINTVL, in seconds;
# 0 selects the system default
tcp_keepalives_count = 10 # TCP_KEEPCNT;
# 0 selects the system default
#------------------------------------------------------------------------------
# RESOURCE USAGE (except WAL)
#------------------------------------------------------------------------------
# - Memory -
# 1/4 主机内存
shared_buffers = 24GB # min 128kB
# (change requires restart)
# 当不使用huge page，并且连接数大于3000时，建议shared buffer不要超过48G
# 建议shared buffer设置超过32GB时 使用大页，页大小 /proc/meminfo Hugepagesize
huge_pages = try # on, off, or try
# (change requires restart)
#temp_buffers = 8MB # min 800kB
# 如果用户需要使用两阶段提交，需要设置为大于0，建议与max_connections一样大
#max_prepared_transactions = 0 # zero disables the feature
# (change requires restart)
# Caution: it is not advisable to set max_prepared_transactions nonzero unless
# you actively intend to use prepared transactions.
# 可以在会话中设置，如果有大量JOIN，聚合操作，并且期望使用hash agg或hash join。
# 可以设大一些，但是不建议大于 四分之一内存除以最大连接数 .
# (一条QUERY中可以使用多倍WORK_MEM，与执行计划中的NODE有关)
# 建议给一个输入，AP模式TP模式OR混合模式。三种模式使用三种不同的计算公式
work_mem = 8MB # min 64kB
# min( 2G, (1/4 主机内存)/autovacuum_max_workers )
maintenance_work_mem = 2GB # 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 # the default is the first option
# supported by the operating system:
# posix
# sysv
# windows
# mmap
# use none to disable dynamic shared memory
# (change requires restart)
# - Disk -
# 如果需要限制临时文件使用量，可以设置。
# 例如防止有异常的递归调用，无限使用临时文件。
#temp_file_limit = -1 # limits per-process temp file space
# in kB, or -1 for no limit
# - Kernel Resource Usage -
## 如果你的数据库有非常多小文件（比如有几十万以上的表，还有索引等，并且每张表都会被访问到时），
# 建议FD可以设多一些，避免进程需要打开关闭文件。
## 但是不要大于前面章节系统设置的ulimit -n(open files)
# max_files_per_process=655360
#max_files_per_process = 1000 # min 25
# (change requires restart)
# 需要加载什么LIB，预先加载，对于经常访问的库也建议预加载，例如postgis
shared_preload_libraries = 'pg_stat_statements,auto_explain' # (change requires restart)
# - Cost-Based Vacuum Delay -
vacuum_cost_delay = 0 # 0-100 milliseconds
#vacuum_cost_page_hit = 1 # 0-10000 credits
vacuum_cost_page_miss = 5 # 0-10000 credits
vacuum_cost_page_dirty = 10 # 0-10000 credits
# io很好，CPU核数很多的机器，设大一些
vacuum_cost_limit = 10000 # 1-10000 credits
# - Background Writer -
bgwriter_delay = 10ms # 10-10000ms between rounds
bgwriter_lru_maxpages = 500 # 0-1000 max buffers written/round
bgwriter_lru_multiplier = 5.0 # 0-10.0 multiplier on buffers scanned/round
# IO非常强悍的机器，可以考虑设置为0
#bgwriter_flush_after = 512kB # measured in pages, 0 disables
# - Asynchronous Behavior -
effective_io_concurrency = 0 # 1-1000; 0 disables prefetching
# wal sender, user 动态fork的process, parallel worker等都算作 worker process, 所以你需要设置足够大.
max_worker_processes = 128 # (change requires restart)
# 如果需要使用并行查询，设置为大于1 ，不建议超过 主机cores-2
max_parallel_workers_per_gather = 0 # taken from max_parallel_workers
# 如果需要使用并行查询，设置为大于1 ，不建议超过 主机cores-2
# 必须小于 max_worker_processes
max_parallel_workers = 8 # maximum number of max_worker_processes that
# can be used in parallel queries
# 开启后有性能影响，但是如果你的系统中有不可预知的长事务，并且希望数据库不因长事务导致垃圾膨胀，则可以设置。
#old_snapshot_threshold = -1 # 1min-60d; -1 disables; 0 is immediate
# (change requires restart)
#backend_flush_after = 0 # measured in pages, 0 disables
#------------------------------------------------------------------------------
# WRITE AHEAD LOG
#------------------------------------------------------------------------------
# - Settings -
# 需要物理备库设置为replica，需要逻辑订阅或逻辑备库则设置为logical
wal_level = replica # minimal, replica, or logical
# (change requires restart)
#fsync = on # flush data to disk for crash safety
# (turning this off can cause
# unrecoverable data corruption)
# 如果双节点，设置为ON，如果是多副本，同步模式，建议设置为remote_write。
# 如果磁盘性能很差，并且是OLTP业务。可以考虑设置为off降低COMMIT的RT，提高吞吐(设置为OFF时，可能丢失部分XLOG RECORD)
synchronous_commit = on # synchronization level;
# off, local, remote_write, remote_apply, or on
# 建议使用pg_test_fsync测试后，决定用哪个最快。通常LINUX下open_datasync比较快。
#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
# 如果文件系统支持COW例如ZFS，则建议设置为OFF。 如果文件系统可以保证datafile block size的原子写，在对齐后也可以设置为OFF。
#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
# (change requires restart)
# 建议 min( 512MB, shared_buffers/32 )
wal_buffers = -1 # min 32kB, -1 sets based on shared_buffers
# (change requires restart)
# 如果设置了synchronous_commit = off，可以设置wal_writer_delay
wal_writer_delay = 10ms # 1-10000 milliseconds
wal_writer_flush_after = 1MB # measured in pages, 0 disables
# 如果synchronous_commit=on, 并且已知业务系统为高并发，对数据库有写操作的小事务，则可以设置commit_delay来实现分组提交，合并WAL FSYNCIO 。
#commit_delay = 0 # range 0-100000, in microseconds
# 同时处于提交状态的事务数超过commit_siblings时，使用分组提交
#commit_siblings = 5 # range 1-1000
# - Checkpoints -
# 不建议频繁做检查点，否则XLOG会产生很多的FULL PAGE WRITE(when full_page_writes=on)。
checkpoint_timeout = 30min # range 30s-1d
# 建议等于SHARED BUFFER，或2倍。
# 同时需要考虑崩溃恢复时间, 越大，检查点可能拉越长导致崩溃恢复耗时越长。但是越小，开启FPW时，WAL日志写入量又越大。 建议采用COW文件系统，关闭FPW。
max_wal_size = 256GB
# 建议是SHARED BUFFER的2分之一
min_wal_size = 64GB
# 硬盘好的情况下，可以让检查点快速结束，恢复时也可以快速达到一致状态。否则建议0.5~0.9
checkpoint_completion_target = 0.1 # checkpoint target duration, 0.0 - 1.0
# IO很好的机器，不需要考虑平滑调度, 否则建议128~256kB
#checkpoint_flush_after = 256kB # measured in pages, 0 disables
#checkpoint_warning = 30s # 0 disables
# - Archiving -
# 建议默认打开，因为修改它需要重启实例
archive_mode = on # enables archiving; off, on, or always
# (change requires restart)
# 后期再修改，如 'test ! -f /disk1/digoal/arch/%f && cp %p /disk1/digoal/arch/%f'
archive_command = '/bin/date' # 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
#------------------------------------------------------------------------------
# REPLICATION
#------------------------------------------------------------------------------
# - Sending Server(s) -
# Set these on the master and on any standby that will send replication data.
# 同时需要几个流复制连接，根据实际需求设定
max_wal_senders = 8 # max number of walsender processes
# (change requires restart)
# 根据实际情况设置保留WAL的数量，主要是防止过早的清除WAL，导致备库因为主库的WAL清除而中断。根据实际情况设定。
wal_keep_segments = 0 # in logfile segments, 16MB each; 0 disables
#wal_sender_timeout = 60s # in milliseconds; 0 disables
# 根据实际情况设置需要创建多少replication slot
# 建议大于等于max_wal_senders
#max_replication_slots = 10 # max number of replication slots
# (change requires restart)
#track_commit_timestamp = off # collect timestamp of transaction commit
# (change requires restart)
# - Master Server -
# These settings are ignored on a standby server.
# 如果有2个或2个以上的备库，可以考虑使用同步多副本模式。 根据实际情况设置
[《PostgreSQL 一主多从(多副本,强同步)简明手册 - 配置、压测、监控、切换、防脑裂、修复、0丢失 - 珍藏级》](201803/20180326_01.md)
#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
# (change requires restart)
max_standby_archive_delay = 300s # max delay before canceling queries
# when reading WAL from archive;
# -1 allows indefinite delay
max_standby_streaming_delay = 300s # max delay before canceling queries
# when reading streaming WAL;
# -1 allows indefinite delay
wal_receiver_status_interval = 1s # send replies at least this often
# 0 disables
# 建议关闭，以免备库长事务导致 主库无法回收垃圾而膨胀。
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 -
# [《PostgreSQL 10.0 preview 逻辑订阅 - 原理与最佳实践》](201702/20170227_01.md)
# These settings are ignored on a publisher.
# 必须小于 max_worker_processes
#max_logical_replication_workers = 4 # taken from max_worker_processes
# (change requires restart)
#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
# 离散IO很好的机器（例如ssd, nvme ssd），不需要考虑离散和顺序扫描的成本差异
random_page_cost = 1.1 # 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
# 扣掉会话连接RSS，shared buffer, autovacuum worker, 剩下的都是OS可用的CACHE。
effective_cache_size = 400GB
# - 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 = 'csvlog' # Valid values are combinations of
# stderr, csvlog, syslog, and eventlog,
# depending on platform. csvlog
# requires logging_collector to be on.
# This is used when logging to stderr:
logging_collector = on # Enable capturing of stderr and csvlog
# into log files. Required to be on for
# csvlogs.
# (change requires restart)
# These are only used if logging_collector is on:
#log_directory = 'log' # directory where log files are written,
# can be absolute or relative to PGDATA
#log_filename = 'postgresql-%Y-%m-%d_%H%M%S.log' # log file name pattern,
# can include strftime() escapes
#log_file_mode = 0600 # creation mode for log files,
# begin with 0 to use octal notation
log_truncate_on_rotation = on # If on, an existing log file with the
# same name as the new log file will be
# truncated rather than appended to.
# But such truncation only occurs on
# time-driven rotation, not on restarts
# or size-driven rotation. Default is
# off, meaning append to existing files
# in all cases.
#log_rotation_age = 1d # Automatic rotation of logfiles will
# happen after that time. 0 disables.
#log_rotation_size = 10MB # Automatic rotation of logfiles will
# happen after that much log output.
# 0 disables.
# These are relevant when logging to syslog:
#syslog_facility = 'LOCAL0'
#syslog_ident = 'postgres'
#syslog_sequence_numbers = on
#syslog_split_messages = on
# This is only relevant when logging to eventlog (win32):
# (change requires restart)
#event_source = 'PostgreSQL'
# - When to Log -
#client_min_messages = notice # values in order of decreasing detail:
# debug5
# debug4
# debug3
# debug2
# debug1
# log
# notice
# warning
# error
#log_min_messages = warning # values in order of decreasing detail:
# debug5
# debug4
# debug3
# debug2
# debug1
# info
# notice
# warning
# error
# log
# fatal
# panic
#log_min_error_statement = error # values in order of decreasing detail:
# debug5
# debug4
# debug3
# debug2
# debug1
# info
# notice
# warning
# error
# log
# fatal
# panic (effectively off)
# 根据实际情况设定，例如业务上认为5秒以上是慢SQL，那么就设置为5秒。
log_min_duration_statement = 5s # -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 = on
# 如果业务是短连接，建议设置为OFF，否则建议设置为ON
log_connections = off
# 如果业务是短连接，建议设置为OFF，否则建议设置为ON
log_disconnections = off
#log_duration = off
log_error_verbosity = verbose # terse, default, or verbose messages
#log_hostname = off
#log_line_prefix = '%m [%p] ' # special values:
# %a = application name
# %u = user name
# %d = database name
# %r = remote host and port
# %h = remote host
# %p = process ID
# %t = timestamp without milliseconds
# %m = timestamp with milliseconds
# %n = timestamp with milliseconds (as a Unix epoch)
# %i = command tag
# %e = SQL state
# %c = session ID
# %l = session line number
# %s = session start timestamp
# %v = virtual transaction ID
# %x = transaction ID (0 if none)
# %q = stop here in non-session
# processes
# %% = '%'
# e.g. '<%u%%%d> '
log_lock_waits = on # log lock waits >= deadlock_timeout
# 如果需要审计SQL，则可以设置为all
log_statement = 'ddl' # none, ddl, mod, all
#log_replication_commands = off
log_temp_files = 1GB # log temporary files equal or larger
# than the specified size in kilobytes;
# -1 disables, 0 logs all temp files
log_timezone = 'PRC'
# - Process Title -
#cluster_name = '' # added to process titles if nonempty
# (change requires restart)
#update_process_title = on
#------------------------------------------------------------------------------
# RUNTIME STATISTICS
#------------------------------------------------------------------------------
# - Query/Index Statistics Collector -
#track_activities = on
#track_counts = on
# 跟踪IO耗时会带来一定的性能影响，默认是关闭的
# 如果需要统计IO的时间开销，设置为ON
track_io_timing = off
#track_functions = none # none, pl, all
#track_activity_query_size = 1024 # (change requires restart)
#stats_temp_directory = '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 = 0 # -1 disables, 0 logs all actions and
# their durations, > 0 logs only
# actions running at least this number
# of milliseconds.
# CPU核多，并且IO好的情况下，可多点，但是注意最多可能消耗这么多内存：
# autovacuum_max_workers * autovacuum mem(autovacuum_work_mem)，
# 会消耗较多内存，所以内存也要有基础。
# 当DELETE\UPDATE非常频繁时，建议设置多一点，防止膨胀严重
autovacuum_max_workers = 6 # max number of autovacuum subprocesses
# (change requires restart)
# 建议不要太高频率，否则会因为vacuum产生较多的XLOG。或者在某些垃圾回收不掉的情况下(例如长事务、feed back on，等)，导致一直触发vacuum，CPU和IO都会升高
[《PostgreSQL垃圾回收代码分析 - why postgresql cann't reclaim tuple is HEAPTUPLE_RECENTLY_DEAD》](201505/20150503_01.md)
[《PostgreSQL物理"备库"的哪些操作或配置，可能影响"主库"的性能、垃圾回收、IO波动》](201704/20170410_03.md)
#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
# 除了设置较大的FREEZE值。
# 还是需要注意FREEZE风暴 [《PostgreSQL Freeze 风暴预测续 - 珍藏级SQL》](201804/20180411_01.md)
# 表级定制freeze
autovacuum_freeze_max_age = 1500000000 # maximum XID age before forced vacuum
# (change requires restart)
autovacuum_multixact_freeze_max_age = 1600000000 # maximum multixact age
# before forced vacuum
# (change requires restart)
autovacuum_vacuum_cost_delay = 0ms # 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'
# 可以用来防止风暴，但是不建议全局设置
statement_timeout = 0 # in milliseconds, 0 is disabled
# 执行DDL时，建议加上超时
#lock_timeout = 0 # in milliseconds, 0 is disabled
# 空闲中事务自动清理，根据业务实际情况设置
idle_in_transaction_session_timeout = 15min # in milliseconds, 0 is disabled
#vacuum_freeze_min_age = 50000000
vacuum_freeze_table_age = 1450000000
#vacuum_multixact_freeze_min_age = 5000000
vacuum_multixact_freeze_table_age = 1450000000
#bytea_output = 'hex' # hex, escape
#xmlbinary = 'base64'
#xmloption = 'content'
# 限制GIN扫描的返回结果集大小，在想限制超多匹配的返回时可以设置
#gin_fuzzy_search_limit = 0
# GIN索引pending list的大小
#gin_pending_list_limit = 4MB
# - Locale and Formatting -
datestyle = 'iso, ymd'
#intervalstyle = 'postgres'
timezone = 'PRC'
#timezone_abbreviations = 'Default' # Select the set of available time zone
# abbreviations. Currently, there are
# Default
# Australia (historical usage)
# India
# You can create your own file in
# share/timezonesets/.
#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 = 'C' # locale for system error message
# strings
lc_monetary = 'C' # locale for monetary formatting
lc_numeric = 'C' # locale for number formatting
lc_time = 'C' # locale for time formatting
# default configuration for text search
default_text_search_config = 'pg_catalog.english'
# - Other Defaults -
#dynamic_library_path = '$libdir'
#local_preload_libraries = ''
#session_preload_libraries = ''
#------------------------------------------------------------------------------
# LOCK MANAGEMENT
#------------------------------------------------------------------------------
#deadlock_timeout = 1s
#max_locks_per_transaction = 64 # min 10
# (change requires restart)
#max_pred_locks_per_transaction = 64 # min 10
# (change requires restart)
#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
#------------------------------------------------------------------------------
# VERSION/PLATFORM COMPATIBILITY
#------------------------------------------------------------------------------
# - Previous PostgreSQL Versions -
#array_nulls = on
#backslash_quote = safe_encoding # on, off, or safe_encoding
#default_with_oids = off
# [《PostgreSQL 转义、UNICODE、与SQL注入》](201704/20170402_01.md)
#escape_string_warning = on
#lo_compat_privileges = off
#operator_precedence_warning = off
#quote_all_identifiers = off
#standard_conforming_strings = on
#synchronize_seqscans = on
# - Other Platforms and Clients -
#transform_null_equals = off
#------------------------------------------------------------------------------
# ERROR HANDLING
#------------------------------------------------------------------------------
#exit_on_error = off # terminate session on any error?
#restart_after_crash = on # reinitialize after backend crash?
#------------------------------------------------------------------------------
# CONFIG FILE INCLUDES
#------------------------------------------------------------------------------
# These options allow settings to be loaded from files other than the
# default postgresql.conf.
#include_dir = 'conf.d' # include files ending in '.conf' from
# directory 'conf.d'
#include_if_exists = 'exists.conf' # include file only if it exists
#include = 'special.conf' # include file
#------------------------------------------------------------------------------
# CUSTOMIZED OPTIONS
#------------------------------------------------------------------------------
# Add settings for extensions here
可以给开发者开放的建议配置
# 允许用户取值： -1 或 大于102400
#temp_file_limit = -1 # limits per-process temp file space
# in kB, or -1 for no limit
# 允许用户取值： >=0 , <= 规格CPU个数-2
max_parallel_workers_per_gather = 0 # taken from max_parallel_workers
# 允许用户取值： >=0 , <= 规格CPU个数-2，必须小于 max_worker_processes
max_parallel_workers = 8 # maximum number of max_worker_processes that
# can be used in parallel queries
# 允许用户取值： -1 或 1min ~ 1d
#old_snapshot_threshold = -1 # 1min-60d; -1 disables; 0 is immediate
# (change requires restart)
# 允许用户取值： replica 或 replica
wal_level = replica # minimal, replica, or replica
# (change requires restart)
# 如果双节点、单节点版本，允许用户取值： off or on
# 如果是多副本，允许用户取值： remote_write, remote_apply or on
synchronous_commit = on # synchronization level;
# off, local, remote_write, remote_apply, or on
# 允许用户取值： 0 ~ 100
#commit_delay = 0 # range 0-100000, in microseconds
# 允许用户取值： 1 ~ 50
#commit_siblings = 5 # range 1-1000
# 允许用户取值： 5min ~ 120min
checkpoint_timeout = 30min # range 30s-1d
# 允许用户取值： 0.1 ~ 0.9
checkpoint_completion_target = 0.1 # checkpoint target duration, 0.0 - 1.0
# 允许用户取值： 128 ~ 8192 约 128GB
wal_keep_segments = 0 # in logfile segments, 16MB each; 0 disables
# 允许用户取值： 0 或 5s ~ 60s
#wal_sender_timeout = 60s # in milliseconds; 0 disables
# 允许用户取值： 0 ~ 1000000
#vacuum_defer_cleanup_age = 0 # number of xacts by which cleanup is delayed
# 只读节点开放时，允许用户设置只读节点参数
# 允许用户取值： 0 ~ 2h
max_standby_archive_delay = 300s # max delay before canceling queries
# when reading WAL from archive;
# -1 allows indefinite delay
max_standby_streaming_delay = 300s # max delay before canceling queries
# when reading streaming WAL;
# -1 allows indefinite delay
# 允许用户取值： 0 ~ 16，必须小于 max_worker_processes
#max_logical_replication_workers = 4 # taken from max_worker_processes
# (change requires restart)
# 允许用户取值： 0 ~ 16，必须小于等于 max_logical_replication_workers
#max_sync_workers_per_subscription = 2 # taken from max_logical_replication_workers
# 允许用户取值： 100ms ~ 60s
log_min_duration_statement = 5s # -1 is disabled, 0 logs all statements
# and their durations, > 0 logs only
# statements running at least this number
# of milliseconds
# 允许用户取值： -1 , 10MB ~ 10GB
#log_temp_files = -1 # log temporary files equal or larger
# than the specified size in kilobytes;
# -1 disables, 0 logs all temp files
# 允许用户取值： 15s ~ 5min
#autovacuum_naptime = 1min # time between autovacuum runs
# 允许用户取值： 1.5亿 ~ 15亿
autovacuum_freeze_max_age = 1500000000 # maximum XID age before forced vacuum
# (change requires restart)
# 允许用户取值： 1.5亿 ~ 15亿
autovacuum_multixact_freeze_max_age = 1600000000 # maximum multixact age
# before forced vacuum
# (change requires restart)
# 允许用户取值： 0 ~ 100ms
autovacuum_vacuum_cost_delay = 0ms # default vacuum cost delay for
# autovacuum, in milliseconds;
# -1 means use vacuum_cost_delay
# 允许用户取值： -1 ~ 10000
autovacuum_vacuum_cost_limit = -1 # default vacuum cost limit for
# autovacuum, -1 means use
# vacuum_cost_limit
# 允许用户取值： 0 或 1s ~ 3600s
statement_timeout = 0 # in milliseconds, 0 is disabled
# 允许用户取值： 0 或 1s ~ 60s
#lock_timeout = 0 # in milliseconds, 0 is disabled
# 允许用户取值： 0 或 5s ~ 300s
idle_in_transaction_session_timeout = 15min # in milliseconds, 0 is disabled
# 允许用户取值： 1.5亿 ~ 15亿
vacuum_freeze_table_age = 1450000000
vacuum_multixact_freeze_table_age = 1450000000
# 允许用户取值： hex, escape
#bytea_output = 'hex' # hex, escape
# 允许用户取值： 0 ~ 100万
#gin_fuzzy_search_limit = 0
# 允许用户设置，设置为数据库允许的值
datestyle = 'iso, ymd'
#intervalstyle = 'postgres'
timezone = 'PRC'
#timezone_abbreviations = 'Default' # Select the set of available time zone
# abbreviations. Currently, there are
# Default
# Australia (historical usage)
# India
# You can create your own file in
# share/timezonesets/.
#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 = 'C' # locale for system error message
# strings
lc_monetary = 'C' # locale for monetary formatting
lc_numeric = 'C' # locale for number formatting
lc_time = 'C' # locale for time formatting
#backslash_quote = safe_encoding # on, off, or safe_encoding
#escape_string_warning = on
#standard_conforming_strings = on
#transform_null_equals = off
内存使用评估
# 1/4 主机内存
shared_buffers = 24GB
#temp_buffers = 8MB
# 可以在会话中设置，如果有大量JOIN，聚合操作，并且期望使用hash agg或hash join。
# 可以设大一些，但是不建议大于 四分之一内存除以最大连接数 .
# (一条QUERY中可以使用多倍WORK_MEM，与执行计划中的NODE有关)
work_mem = 8MB
# min( 2G, (1/4 主机内存)/autovacuum_max_workers )
maintenance_work_mem = 2GB
#autovacuum_work_mem = -1
# 建议 min( 512MB, shared_buffers/32 )
wal_buffers = -1
autovacuum_max_workers = 6
max_connections = 2000
总memory使用评估:
shared buffer shared_buffers : 24GB
vacuum autovacuum_work_mem * autovacuum_max_workers 或 maintenance_work_mem * autovacuum_max_workers : 2G*6=12G
create index maintenance_work_mem * 同时创建索引的并发 : 2G * 8 = 16G (假设同时创建索引的进程为6个)
group by, sort, hash agg, hash join 并发使用这些操作的SQL * work_mem : (max_connections/10)*8MB = 1.6GB (假设十分之一的连接，每条SQL只用一份work_mem, 实际上复杂SQL可能用多份)
wal buffer wal_buffers : 16MB
connection : max_connections * 10MB = 20GB (假设每个连接使用10MB，实际上可能更多，relcache, syscache，与访问的对象有关)
page table : 页表，与shared_buffers，并发连接，以及连接TOUCH的SHARED BUFFER数，是否使用HUGE PAGE有关