#------------------------------------------------------------------------------
# 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 -
# 監聽
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)
# 根據業務需求設定監聽端口
port = 1921 # (change requires restart)
# 比較安全的值：建議不要大於 200 * 四分之一物理內存(GB)， 例如四分之一物理內存爲16G，則建議不要超過3200.
# (假設平均一個連接耗費5MB。 實際上syscache很大、SQL 使用到WORK_MEM，未使用hugepage並且訪問到大量shared buffer page時，可能消耗更多內存)
# 如果業務有更多併發連接，可以使用連接池，例如pgbouncer
# [《PostgreSQL relcache在長連接應用中的內存霸佔"坑"》](201607/20160709_01.md)
# max_connections 公式：物理內存(GB)*1000*(1/4)/5
max_connections = 2000 # (change requires restart)
# 爲超級用戶保留多少個連接
superuser_reserved_connections = 10 # (change requires restart)
# $PGDATA, /tmp中 創建unix socket監聽
unix_socket_directories = '., /tmp' # comma-separated list of directories
# (change requires restart)
#unix_socket_group = '' # (change requires restart)
# 除了OWNER和超級用戶，其他用戶無法從/tmp unix socket連接該實例
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)
# - TCP Keepalives -
# see "man 7 tcp" for details
# 如果你連接數據庫空閒一段時間會端口，可能是網絡中存在會話超時的設備，建議可以設置一下這個心跳時間，TCP心跳間隔會縮短到60秒。
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
# - Authentication -
#authentication_timeout = 1min # 1s-600s
# md5 or scram-sha-256 # 如果用戶密碼的MD5會泄露，建議使用scram-sha-256，但是相互不兼容，請注意。
# [《PostgreSQL 10.0 preview 安全增強 - SASL認證方法 之 scram-sha-256 安全認證機制》](201703/20170309_01.md)
password_encryption = md5 # md5 or scram-sha-256
#db_user_namespace = off
# GSSAPI using Kerberos
#krb_server_keyfile = ''
#krb_caseins_users = off
# - SSL -
#ssl = off
#ssl_ca_file = ''
#ssl_cert_file = 'server.crt'
#ssl_crl_file = ''
#ssl_key_file = 'server.key'
#ssl_ciphers = 'HIGH:MEDIUM:+3DES:!aNULL' # allowed SSL ciphers
#ssl_prefer_server_ciphers = on
#ssl_ecdh_curve = 'prime256v1'
#ssl_dh_params_file = ''
#ssl_passphrase_command = ''
#ssl_passphrase_command_supports_reload = off
#------------------------------------------------------------------------------
# RESOURCE USAGE (except WAL)
#------------------------------------------------------------------------------
# - Memory -
# 1/4 主機內存
# shared_buffers 公式： IF use hugepage: 主機內存*(1/4) ELSE: min(32GB, 主機內存*(1/4))
# [《PostgreSQL Huge Page 使用建議 - 大內存主機、實例注意》](201803/20180325_02.md)
shared_buffers = 24GB # min 128kB
# (change requires restart)
# 建議shared buffer設置超過32GB時 使用大頁，頁大小 /proc/meminfo Hugepagesize
huge_pages = try # on, off, or try
# (change requires restart)
#temp_buffers = 8MB # min 800kB
# 如果用戶需要使用兩階段提交，需要設置爲大於0，建議與max_connections一樣大
# max_prepared_transactions 公式： max_prepared_transactions=max_connections
max_prepared_transactions = 2000 # 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.
# 可以在會話中設置，如果有大量JOIN，聚合操作，並且期望使用hash agg或hash join。 (排序，HASH都會用到work_mem)
# 可以設大一些，但是不建議大於 四分之一內存除以最大連接數 .
# (一條QUERY中可以使用多倍WORK_MEM，與執行計劃中的NODE有關)
# work_mem 公式： max(min(物理內存/4096, 64MB), 4MB)
work_mem = 8MB # min 64kB
# 創建索引時使用的內存空間。
# maintenance_work_mem 公式： min( 8G, (主機內存*1/8)/max_parallel_maintenance_workers )
maintenance_work_mem = 2GB # min 1MB
# 在對一張表進行垃圾回收時，用於緩存垃圾版本的ctid，
# 如果autovacuum work mem填滿了，則VACUUM需要進入索引垃圾回收階段，掃描索引（因此爲了避免索引被多次掃描，需要緩存住一張表的所有垃圾TUPLE的CTID）。
# 一張表（細到單個最底層分區）垃圾回收結束後釋放。
# [《PostgreSQL 垃圾回收參數優化之 - maintenance_work_mem , autovacuum_work_mem》](201902/20190226_01.md)
# autovacuum_work_mem 公式： min( 8G, (主機內存*1/8)/autovacuum_max_workers )
autovacuum_work_mem = 1GB # 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 -
# 如果需要限制臨時文件使用量，可以設置。
# 例如, 防止有異常的遞歸調用，無限使用臨時文件。
#temp_file_limit = -1 # limits per-process temp file space
# in kB, or -1 for no limit
# - Kernel Resources -
## 如果你的數據庫有非常多小文件（比如有幾十萬以上的表，還有索引等，並且每張表都會被訪問到時），
# 建議FD可以設多一些，避免進程需要打開關閉文件。
## 但是不要大於前面章節系統設置的ulimit -n(open files)
# max_files_per_process=655360
#max_files_per_process = 1000 # min 25
# (change requires restart)
# - Cost-Based Vacuum Delay -
# 如果你的系統IO非常好，則可以關閉vacuum delay ， 避免因爲垃圾回收任務週期長導致的膨脹。
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
# io很好，CPU核數很多的機器，設大一些。如果設置了vacuum_cost_delay = 0 ，則這個不需要配置
vacuum_cost_limit = 10000 # 1-10000 credits
# - Background Writer -
bgwriter_delay = 10ms # 10-10000ms between rounds
bgwriter_lru_maxpages = 1000 # max buffers written/round, 0 disables
bgwriter_lru_multiplier = 10.0 # 0-10.0 multiplier on buffers scanned/round
bgwriter_flush_after = 512kB # measured in pages, 0 disables
# - Asynchronous Behavior -
effective_io_concurrency = 0 # 1-1000; 0 disables prefetching
# wal sender, user 動態fork的process, parallel worker等都算作 worker process, 所以你需要設置足夠大.
max_worker_processes = 256 # (change requires restart)
# 如果需要使用並行創建索引，設置爲大於1 ，不建議超過 主機cores-4
# max_parallel_maintenance_workers 公式： min( max(2, CPU核數/2) , 16 )
max_parallel_maintenance_workers = 6 # taken from max_parallel_workers
# 如果需要使用並行查詢，設置爲大於1 ，不建議超過 主機cores-4
# max_parallel_workers_per_gather 公式： min( max(2, CPU核數-4) , 24 )
max_parallel_workers_per_gather = 0 # taken from max_parallel_workers
# leader 是否與work process一起參與並行計算，如果ON，則並行度會默認+1。
parallel_leader_participation = on
# 如果需要使用並行查詢，設置爲大於1 ，不建議超過 主機cores-2
# 必須小於 max_worker_processes
# max_parallel_workers 公式： max(2, CPU核數-4)
max_parallel_workers = 32 # maximum number of max_worker_processes that
# can be used in parallel operations
# 是否啓用snapshot too old技術，避免長事務導致的膨脹
# 會導致性能一定的下降，約8%
old_snapshot_threshold = 6h # 1min-60d; -1 disables; 0 is immediate
# (change requires restart)
#backend_flush_after = 256 # measured in pages, 0 disables
#------------------------------------------------------------------------------
# WRITE-AHEAD LOG
#------------------------------------------------------------------------------
# - Settings -
# 需要流複製物理備庫、歸檔、時間點恢復時，設置爲replica，需要邏輯訂閱或邏輯備庫則設置爲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)
# 如果雙節點，設置爲ON，如果是多副本，同步模式，建議設置爲remote_write。
# 如果磁盤性能很差，並且是OLTP業務。可以考慮設置爲off降低COMMIT的RT，提高吞吐(設置爲OFF時，可能丟失部分XLOG RECORD)
synchronous_commit = off # synchronization level;
# off, local, remote_write, remote_apply, or on
# 建議使用pg_test_fsync測試後，決定用哪個最快。通常LINUX下open_datasync比較快。
#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
# 如果文件系統支持COW例如ZFS，則建議設置爲OFF。
# 如果文件系統可以保證datafile block size的原子寫，在文件系統與IO系統對齊後也可以設置爲OFF。
# 如果底層存儲能保證IO的原子寫，也可以設置爲OFF。
full_page_writes = on # recover from partial page writes
# 當寫FULL PAGE WRITE的io是瓶頸時建議開啓
wal_compression = on # enable compression of full-page writes
# 如果要使用pg_rewind，flashback 時間線，需要打開這個功能
# [《PostgreSQL pg_rewind，時間線修復，腦裂修復，flashback - 從庫開啓讀寫後，回退爲只讀從庫。異步主從發生角色切換後，主庫rewind爲新主庫的從庫》](201901/20190128_02.md)
#wal_log_hints = off # also do full page writes of non-critical updates
# (change requires restart)
# 建議 min( WAL segment size(默認16MB) , shared_buffers/32 )
wal_buffers = 16MB # min 32kB, -1 sets based on shared_buffers
# (change requires restart)
# 如果設置了synchronous_commit = off，建議設置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, 並且已知業務系統爲高併發，對數據庫有寫操作的小事務，則可以設置commit_delay來實現分組提交，合併WAL FSYNCIO 。
# 分組提交
#commit_delay = 10 # range 0-100000, in microseconds
# 同時處於提交狀態的事務數超過commit_siblings時，使用分組提交
#commit_siblings = 5 # range 1-1000
# - Checkpoints -
# 不建議頻繁做檢查點，否則XLOG會產生很多的FULL PAGE WRITE(when full_page_writes=on)。
checkpoint_timeout = 30min # range 30s-1d
# 建議等於SHARED BUFFER，或2倍。
# 同時需要考慮崩潰恢復時間, 越大，檢查點可能拉越長導致崩潰恢復耗時越長。但是越小，開啓FPW時，WAL日誌寫入量又越大。 建議採用COW文件系統，關閉FPW。
# max_wal_size 公式： shared_buffers*2
max_wal_size = 48GB
# 建議是SHARED BUFFER的2分之一
# min_wal_size 公式： shared_buffers/2
min_wal_size = 12GB
# 硬盤好(nvme ssd)的情況下，值越小可以讓檢查點快速結束，恢復時也可以快速達到一致狀態。否則建議0.5~0.9
# 如果有hot standby作爲HA節點，這個值也可以設置爲0.5~0.9 避免寫高峯時CHECKPOINT對寫帶來的衝擊。
checkpoint_completion_target = 0.2 # checkpoint target duration, 0.0 - 1.0
# IO很好的機器，不需要考慮平滑調度, 否則建議128~256kB
checkpoint_flush_after = 256kB # measured in pages, 0 disables
#checkpoint_flush_after = 0 # measured in pages, 0 disables
#checkpoint_warning = 30s # 0 disables
# - Archiving -
# 建議默認打開，因爲修改它需要重啓實例
# 打開後，一個WAL文件寫滿後，會在pg_wal/archive_status目錄中創建xxxxxx.ready的文件，歸檔命令archive_command正常結束後，會清除這個狀態文件。
archive_mode = on # enables archiving; off, on, or always
# (change requires restart)
# 後期再修改，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 Servers -
# Set these on the master and on any standby that will send replication data.
# 同時允許幾個流複製協議的連接，根據實際需求設定 ，可以設置一個默認值例如64
max_wal_senders = 64 # max number of walsender processes
# (change requires restart)
# 根據實際情況設置保留WAL的數量，主要是防止過早的清除WAL，導致備庫因爲主庫的WAL清除而中斷。根據實際情況設定。
#wal_keep_segments = 0 # in logfile segments; 0 disables
#wal_sender_timeout = 60s # in milliseconds; 0 disables
# 根據實際情況設置需要創建多少replication slot
# 使用slot，可以保證流複製下游沒有接收的WAL會在當前節點永久保留。所以必須留意下游的接收情況，否則可能導致WAL爆倉
# 建議大於等於max_wal_senders
# max_replication_slots 公式： max_replication_slots=max_wal_senders
max_replication_slots = 64 # 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個或2個以上的備庫，可以考慮使用同步多副本模式。 根據實際情況設置
# [《PostgreSQL 一主多從(多副本,強同步)簡明手冊 - 配置、壓測、監控、切換、防腦裂、修復、0丟失 - 珍藏級》](201803/20180326_01.md)
# [《PostgreSQL 雙節點流複製如何同時保證可用性、可靠性(rpo,rto) - （半同步，自動降級方法實踐）》](201901/20190127_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
# 注意，當數據庫有大量的更新、刪除操作時，設置這個值容易導致表膨脹，容易導致VACUUM進程空轉，導致IO和CPU飆升。（特別是autovacuum naptime配置很小時）
#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)
# 當standby的archive replay與standby的用戶SQL請求發生衝突時，在打斷SQL前，允許用戶SQL最長的執行時間. 打斷SQL後，需要等STANDBY APPLY所有archive restore command 的WAL文件，APPLY才允許被繼續打斷。
max_standby_archive_delay = 120s # max delay before canceling queries
# when reading WAL from archive;
# -1 allows indefinite delay
max_standby_streaming_delay = 120s # 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
# 建議關閉，以免備庫長事務導致 主庫無法回收垃圾而膨脹。
[《PostgreSQL物理"備庫"的哪些操作或配置，可能影響"主庫"的性能、垃圾回收、IO波動》](201704/20170410_03.md)
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 -
# 邏輯複製訂閱端節點設置：
# These settings are ignored on a publisher.
# [《PostgreSQL 10.0 preview 邏輯訂閱 - 原理與最佳實踐》](201702/20170227_01.md)
# These settings are ignored on a publisher.
# 必須小於 max_worker_processes
# 包括 apply workers and table synchronization workers
# max_logical_replication_workers 公式： max_logical_replication_workers=max_wal_senders
max_logical_replication_workers = 64 # taken from max_worker_processes
# (change requires restart)
# Maximum number of synchronization workers per subscription. This parameter controls the amount of parallelism of the initial data copy during the subscription initialization or when new tables are added.
# max_sync_workers_per_subscription 公式： min ( 32 , max(2, CPU核數-4) )
max_sync_workers_per_subscription = 8 # 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_parallel_append = on
#enable_seqscan = on
#enable_sort = on
#enable_tidscan = on
# OLAP業務，建議設置爲ON （enable_partitionwise_join， enable_partitionwise_aggregate）
# [《PostgreSQL 並行計算解說 彙總》](201903/20190319_01.md)
enable_partitionwise_join = on
enable_partitionwise_aggregate = on
#enable_parallel_hash = on
#enable_partition_pruning = on
# - Planner Cost Constants -
#seq_page_cost = 1.0 # measured on an arbitrary scale
# 離散IO很好的機器（例如ssd, nvme ssd），不需要考慮離散和順序掃描的成本差異
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
#jit_above_cost = 100000 # perform JIT compilation if available
# and query more expensive, -1 disables
#jit_optimize_above_cost = 500000 # optimize JITed functions if query is
# more expensive, -1 disables
#jit_inline_above_cost = 500000 # attempt to inline operators and
# functions if query is more expensive,
# -1 disables
#min_parallel_table_scan_size = 8MB
#min_parallel_index_scan_size = 512kB
# 扣掉會話連接RSS，shared buffer, autovacuum worker, 剩下的都是OS可用的CACHE。
# effective_cache_size 公式： 主機內存/2
effective_cache_size = 80GB
# - 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
#------------------------------------------------------------------------------
# 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
# 時間格式 http://pubs.opengroup.org/onlinepubs/009695399/functions/strftime.html
# 設置參考 https://www.postgresql.org/docs/11/runtime-config-logging.html#RUNTIME-CONFIG-LOGGING-WHERE
# 日誌保留一週例子，每天一個文件
log_filename = 'postgresql-%a.log' # log file name pattern,
# can include strftime() escapes
# 日誌保留一個月例子，每天一個文件
# log_filename = 'postgresql-%d.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.
# 單個日誌文件最大多大時，被截斷，可以設置一個上限防止日誌無限制增長
log_rotation_size = 1GB
# log_rotation_size = 0 # 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)
# 根據實際情況設定，例如業務上認爲5秒以上是慢SQL，那麼就設置爲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
# 記錄檢查點的詳細統計信息
log_checkpoints = on
# 如果業務是短連接，建議設置爲OFF，否則建議設置爲ON
log_connections = off
# 如果業務是短連接，建議設置爲OFF，否則建議設置爲ON
log_disconnections = off
#log_duration = off
# 記錄錯誤代碼的代碼位置，是什麼代碼輸出的日誌，更好的跟蹤問題
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> '
# 是否打印鎖等待事件
log_lock_waits = on # log lock waits >= deadlock_timeout
# 如果需要審計SQL，則可以設置爲all
log_statement = 'ddl' # none, ddl, mod, all
#log_replication_commands = off
# 當使用的臨時文件超過多大時，打印到日誌中，跟蹤大SQL。
log_temp_files = 256MB # 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
#------------------------------------------------------------------------------
# STATISTICS
#------------------------------------------------------------------------------
# - Query and Index Statistics Collector -
#track_activities = on
#track_counts = on
# 跟蹤IO耗時會帶來一定的性能影響，默認是關閉的
# 如果需要統計IO的時間開銷，設置爲ON
# 建議用pg_test_timing測試一下獲取時間的開銷，如果開銷很大，建議關閉這個時間跟蹤。
track_io_timing = on
# 是否需要跟蹤函數被調用的次數，耗時
track_functions = pl # none, pl, all
# 單條被跟蹤的QUERY最多能存儲多少字節，如果有超長SQL，則日誌中被截斷。 根據需要設置
#track_activity_query_size = 1024 # (change requires restart)
# 相對路徑（$PGDATA）或絕對路徑。用於存儲統計信息的臨時目錄。可以設置爲ram based directory，提高性能
# Pointing this at a RAM-based file system will decrease physical I/O requirements and can lead to improved performance.
#stats_temp_directory = 'pg_stat_tmp'
# - Monitoring -
#log_parser_stats = off
#log_planner_stats = off
#log_executor_stats = off
#log_statement_stats = off
#------------------------------------------------------------------------------
# AUTOVACUUM
#------------------------------------------------------------------------------
# 打開自動垃圾回收
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，並且IO好的情況下，可多點，但是注意最多可能消耗這麼多內存：
# autovacuum_max_workers * autovacuum mem(autovacuum_work_mem)，
# 會消耗較多內存，所以內存也要有基礎。
# 當DELETE\UPDATE非常頻繁時，建議設置多一點，防止膨脹嚴重
# autovacuum_max_workers 公式： max(min( 8 , CPU核數/2 ) , 5)
autovacuum_max_workers = 8 # max number of autovacuum subprocesses
# (change requires restart)
# 建議不要太高頻率，否則會因爲vacuum產生較多的XLOG。或者在某些垃圾回收不掉的情況下(例如長事務、feed back on，等)，導致一直觸發vacuum，CPU和IO都會升高
[《PostgreSQL垃圾回收代碼分析 - why postgresql cann't reclaim tuple is HEAPTUPLE_RECENTLY_DEAD》](201505/20150503_01.md)
[《PostgreSQL物理"備庫"的哪些操作或配置，可能影響"主庫"的性能、垃圾回收、IO波動》](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 = 0.02 # fraction of table size before vacuum
autovacuum_analyze_scale_factor = 0.01 # fraction of table size before analyze
# 除了設置較大的FREEZE值。
# 還是需要注意FREEZE風暴 [《PostgreSQL Freeze 風暴預測續 - 珍藏級SQL》](201804/20180411_01.md)
# 表級定製freeze
[《PostgreSQL 10 CLogControlLock 等待事件分析與優化 - hint bit, freeze, autovacuum, 風暴》](201903/20190319_02.md)
autovacuum_freeze_max_age = 1200000000 # maximum XID age before forced vacuum
# (change requires restart)
autovacuum_multixact_freeze_max_age = 1250000000 # maximum multixact age
# before forced vacuum
# (change requires restart)
# 如果數據庫UPDATE非常頻繁，建議設置爲0。並且建議使用SSD
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
#row_security = on
#default_tablespace = '' # a tablespace name, '' uses the default
# 臨時表的表空間，可以設置多個，輪詢使用。
# 臨時表的表空間，建議爲SSD目錄。速度快。
#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'
# 可以用來防止雪崩，但是不建議全局設置
#statement_timeout = 0 # in milliseconds, 0 is disabled
# 執行DDL時，建議加上超時
# 可以用來防止雪崩
#lock_timeout = 0 # in milliseconds, 0 is disabled
# 空閒中事務自動清理，根據業務實際情況設置
idle_in_transaction_session_timeout = '6h' # in milliseconds, 0 is disabled
#[《PostgreSQL 10 CLogControlLock 等待事件分析與優化 - hint bit, freeze, autovacuum, 風暴》](201903/20190319_02.md)
#vacuum_freeze_min_age = 50000000
vacuum_freeze_table_age = 200000000
#vacuum_multixact_freeze_min_age = 5000000
vacuum_multixact_freeze_table_age = 200000000
# [《PostgreSQL 11 內核優化 - 降低vacuum cleanup階段index scan概率 ( vacuum_cleanup_index_scale_factor , skip index vacuum cleanup stage)》](201902/20190201_03.md)
#vacuum_cleanup_index_scale_factor = 0.1 # fraction of total number of tuples
# before index cleanup, 0 always performs
# index cleanup
#bytea_output = 'hex' # hex, escape
#xmlbinary = 'base64'
#xmloption = 'content'
# 限制GIN掃描的返回結果集大小，在想限制超多匹配的返回時可以設置
#gin_fuzzy_search_limit = 0
# GIN索引pending list的大小
#gin_pending_list_limit = 4MB
# - Locale and Formatting -
datestyle = 'iso, mdy'
#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/.
# 浮點精度擴展值
[《PostgreSQL 浮點精度調整（extra_float_digits）》](201510/20151020_01.md)
#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'
# - Shared Library Preloading -
# 需要加載什麼LIB，預先加載，對於經常訪問的庫也建議預加載，例如postgis
#shared_preload_libraries = 'pg_jieba,pipelinedb' # (change requires restart)
shared_preload_libraries = 'pg_stat_statements'
#local_preload_libraries = ''
#session_preload_libraries = ''
# - Other Defaults -
#dynamic_library_path = '$libdir'
# 是否已編譯JIT特性，如果已編譯，設置爲ON
#jit = off # allow JIT compilation
#jit_provider = 'llvmjit' # JIT implementation to use
#------------------------------------------------------------------------------
# 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 AND PLATFORM COMPATIBILITY
#------------------------------------------------------------------------------
# - Previous PostgreSQL Versions -
#array_nulls = on
#backslash_quote = safe_encoding # on, off, or safe_encoding
#default_with_oids = off
# [《PostgreSQL 轉義、UNICODE、與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 -
# 是否啓用 exp = null 自動轉換爲 exp is null
# https://www.postgresql.org/docs/11/runtime-config-compatible.html#RUNTIME-CONFIG-COMPATIBLE-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
小結
1、固定參數
listen_addresses = '*'
superuser_reserved_connections = 10
unix_socket_directories = '., /tmp'
unix_socket_permissions = 0700
tcp_keepalives_idle = 60
tcp_keepalives_interval = 10
tcp_keepalives_count = 10
password_encryption = md5 # 初始化時指定後，不建議修改。pg_hba.conf 也請使用相應認證方法。 同時需要客戶端支持scram-sha-256認證方法
huge_pages = try
dynamic_shared_memory_type = posix
vacuum_cost_delay = 0
vacuum_cost_limit = 10000
bgwriter_delay = 10ms
bgwriter_lru_maxpages = 1000
bgwriter_lru_multiplier = 10.0
bgwriter_flush_after = 512kB
effective_io_concurrency = 0
max_worker_processes = 256
parallel_leader_participation = on
old_snapshot_threshold = 6h
wal_level = replica
synchronous_commit = off
full_page_writes = on
wal_compression = on
wal_buffers = 16MB
wal_writer_delay = 10ms
wal_writer_flush_after = 1MB
checkpoint_timeout = 30min
checkpoint_completion_target = 0.2
checkpoint_flush_after = 256kB
archive_mode = on
archive_command = '/bin/date'
max_wal_senders = 64
max_replication_slots = 64
hot_standby = on
max_standby_archive_delay = 120s
max_standby_streaming_delay = 120s
wal_receiver_status_interval = 1s
hot_standby_feedback = off
max_logical_replication_workers = 64
enable_partitionwise_join = on
enable_partitionwise_aggregate = on
random_page_cost = 1.1
log_destination = 'csvlog'
logging_collector = on
log_directory = 'log'
log_filename = 'postgresql-%a.log'
log_truncate_on_rotation = on
log_rotation_age = 1d
log_rotation_size = 1GB
log_min_duration_statement = 5s
log_checkpoints = on
log_connections = off
log_disconnections = off
log_error_verbosity = verbose
log_lock_waits = on
log_statement = 'ddl'
log_temp_files = 256MB
track_io_timing = on
track_functions = pl
autovacuum = on
log_autovacuum_min_duration = 0
autovacuum_vacuum_scale_factor = 0.02
autovacuum_analyze_scale_factor = 0.01
autovacuum_freeze_max_age = 1200000000
autovacuum_multixact_freeze_max_age = 1250000000
autovacuum_vacuum_cost_delay = 0ms
idle_in_transaction_session_timeout = '6h'
vacuum_freeze_table_age = 200000000
vacuum_multixact_freeze_table_age = 200000000
default_text_search_config = 'pg_catalog.english'
shared_preload_libraries = 'pg_stat_statements'
deadlock_timeout = 1s
2、環境參數
log_timezone = 'PRC'
datestyle = 'iso, mdy'
timezone = 'PRC'
lc_messages = 'C'
lc_monetary = 'C'
lc_numeric = 'C'
lc_time = 'C'
3、動態參數
port = 1921 # 監聽端口
max_connections = 2000 # 物理內存(GB)*1000*(1/4)/5
shared_buffers = 24GB # IF use hugepage: 主機內存*(1/4) ELSE: min(32GB, 主機內存*(1/4))
max_prepared_transactions = 2000 # max_prepared_transactions=max_connections
work_mem = 8MB # max(min(物理內存/4096, 64MB), 4MB)
maintenance_work_mem = 2GB # min( 8G, (主機內存*1/8)/max_parallel_maintenance_workers )
autovacuum_work_mem = 1GB # min( 8G, (主機內存*1/8)/autovacuum_max_workers )
max_parallel_maintenance_workers = 6 # min( max(2, CPU核數/2) , 16 )
max_parallel_workers_per_gather = 0 # min( max(2, CPU核數-4) , 24 )
max_parallel_workers = 32 # max(2, CPU核數-4)
max_wal_size = 48GB # shared_buffers*2
min_wal_size = 12GB # shared_buffers/2
max_sync_workers_per_subscription = 8 # min ( 32 , max(2, CPU核數-4) )
effective_cache_size = 80GB # 主機內存/2
autovacuum_max_workers = 8 # max(min( 8 , CPU核數/2 ) , 5)
配置例子
64G內存，16核，HUGE PAGE=on，SSD機器
port = 1921 # 監聽端口
max_connections = 3200 # 物理內存(GB)*1000*(1/4)/5
shared_buffers = 16GB # IF use hugepage: 主機內存*(1/4) ELSE: min(32GB, 主機內存*(1/4))
max_prepared_transactions = 3200 # max_prepared_transactions=max_connections
work_mem = 16MB # max(min(物理內存/4096, 64MB), 4MB)
maintenance_work_mem = 1GB # min( 8G, (主機內存*1/8)/max_parallel_maintenance_workers )
autovacuum_work_mem = 1GB # min( 8G, (主機內存*1/8)/autovacuum_max_workers )
max_parallel_maintenance_workers = 8 # min( max(2, CPU核數/2) , 16 )
max_parallel_workers_per_gather = 12 # min( max(2, CPU核數-4) , 24 )
max_parallel_workers = 12 # max(2, CPU核數-4)
max_wal_size = 32GB # shared_buffers*2
min_wal_size = 8GB # shared_buffers/2
max_sync_workers_per_subscription = 12 # min ( 32 , max(2, CPU核數-4) )
effective_cache_size = 32GB # 主機內存/2
autovacuum_max_workers = 8 # max(min( 8 , CPU核數/2 ) , 5)
其他參數值請拷貝以上固定參數與環境參數內容。
pg_hba.conf 數據庫防火牆配置模板
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
local all all trust
# IPv4 local connections:
host all all 127.0.0.1/32 trust
# IPv6 local connections:
host all all ::1/128 trust
# Allow replication connections from localhost, by a user with the
# replication privilege.
local replication all trust
host replication all 127.0.0.1/32 trust
host replication all ::1/128 trust
# 禁止超級用戶從遠程連接
host all postgres 0.0.0.0/0 reject
# 應用連接配置：哪個用戶，從哪裏來，連接什麼數據庫。規則爲使用何種認證方法，或拒絕？
# TYPE DATABASE USER ADDRESS METHOD
# 如果不想挨個配置，可以使用如下配置，允許所有來源，通過任意用戶訪問任意數據庫
host all all 0.0.0.0/0 md5