Re: Postgresql.conf cleanup - Mailing list pgsql-hackers

This time *with* the attachment.


> All,
>
> I'm working on cleaning up postgresql.conf and pg_settings for the
> release.  Attached is a sample WIP.  It's not in patch form because I'm
> not done yet; I've just been editing postgresql.conf and need to fix the
> docs and pg_settings to match.
>
> Issues encountered and changes made:
>
> PostgreSQL.conf
> ----------------
>
> suggestions: added section with the 7 most important obvious settings at
> the top and suggestions on how to calculate them.  If people like this,
> I'll add it to the Tutorial in the docs as well.
>
> seq_scan_cost: this is independant of all of the other _costs.  I can't
> think of any way in which that doesn't make the whole set of costs
> unmanageable.  For example, if you want to change seq_scan_cost in order
> to make query cost more-or-less match up with ms execution time, you
> have to modify all 6 settings.   If we do implement per-tablespace
> costs, then we'll need per-tablespace random_page_cost as well.  Or am I
> missing something?
>
> (change requires restart): this phrase appears over 20 times in the
> notes.  This is enough times to be really repetitive and take up a lot
> of scrolling space, while not actually covering all startup-time
> parameters.  We should either (a) remove all such notes and rely on
> docs, or (b) make an annotation symbol (e.g. *R) and mark 100% of them.
>  Votes?
>
> Vacuum: all vacuum & autovacuum parameters put under their own section.
>
> Client Cost Defaults: this section became a "catch-all" for all userset
> parameters which people weren't sure what to do with.  I've divided it
> into logical subsections, and moved some parameters to other sections
> where they logically belong (for example, explain_pretty_print belongs
> in Query Tuning).
>
> pg_settings issues
> --------------------
>
> transaction_isolation and transaction_read_only appear more than once in
> the pg_settings pseudo_table.   The setting column is supposed to be
> unique.
>
>
> Given the amount of cleanup/improvement which I'm seeing as necessary
> for the GUCs, I'm wondering if I put this off too long for 8.3.
>
> --Josh
>
>
>
>

# -----------------------------
# PostgreSQL configuration file
# -----------------------------
#
# This file consists of lines of the form:
#
#   name = value
#
# (The '=' is optional.)  White space may be used.  Comments are introduced
# with '#' anywhere on a line.  The complete list of option names and
# allowed values can be found in the PostgreSQL documentation.  The
# commented-out settings shown in this file represent the default values.
#
# Please note that re-commenting a setting is NOT sufficient to revert it
# to the default value, unless you restart the server.
#
# Any option can also be given as a command line switch to the server,
# e.g., 'postgres -c log_connections=on'.  Some options can be changed at
# run-time with the 'SET' SQL command.
#
# This file is read on server startup and when the server receives a
# SIGHUP.  If you edit the file on a running system, you have to SIGHUP the
# server for the changes to take effect, or use "pg_ctl reload". Some
# settings, which are marked below, require a server shutdown and restart
# to take effect.
#
# Memory units:  kB = kilobytes MB = megabytes GB = gigabytes
# Time units:    ms = milliseconds s = seconds min = minutes h = hours d = days

#---------------------------------------------------------------------------
# IMPORTANT PERFORMANCE VALUES TO SET
#---------------------------------------------------------------------------

# What follows are some rough recommendations of values which most users
# should set immediately after installation for good performance.  The
# calculations below are "rules of thumb" and are not intended to replace
# knowledgeable tuning. Please see the full documentation and the
# pgsql-performance mailing list for more information and suggestions.
#
# Note that RAM below refers to RAM which is available to PostgreSQL,
# so on shared servers the RAM in the calculation should be reduced from
# total system RAM accordingly.  Settings are listed in the order they
# appear below.
#
# max_connections = no. of concurrent sessions you need to support
# shared_buffers = RAM * 0.2 (this may require system configuration)
# work_mem = ( RAM * 0.5 ) / max_connections, or less
# maintenance_work_mem = RAM/8, up to 256MB
# wal_buffers = 1MB
# max_fsm_pages = expected database size * 0.1
# checkpoint_segments = 8 to 16 if you have the disk space (0.3 to 0.6 GB)
# effective_cache_size = RAM * 0.7


#---------------------------------------------------------------------------
# FILE LOCATIONS
#---------------------------------------------------------------------------

# The default values of these variables are driven from the -D command line
# switch 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 = '(none)'        # write an extra PID file
                    # (change requires restart)


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

# - Connection Settings -

#listen_addresses = 'localhost'        # what IP address(es) to listen on;
                    # comma-separated list of addresses;
                    # defaults to 'localhost', '*' = all
                    # (change requires restart)
#port = 5432                # (change requires restart)
#max_connections = 100            # (change requires restart)
# Note: increasing max_connections costs ~400 bytes of shared memory per
# connection slot, plus lock space (see max_locks_per_transaction).  You
# might also need to raise shared_buffers to support more connections.
#superuser_reserved_connections = 3    # (change requires restart)
#unix_socket_directory = ''        # (change requires restart)
#unix_socket_group = ''            # (change requires restart)
#unix_socket_permissions = 0777        # octal
                    # (change requires restart)
#bonjour_name = ''            # defaults to the computer name
                    # (change requires restart)

# - Security & Authentication -

#authentication_timeout = 1min        # 1s-600s
#ssl = off                # (change requires restart)
#ssl_ciphers = 'ALL:!ADH:!LOW:!EXP:!MD5:@STRENGTH'    # Allowed SSL ciphers
                    # (change requires restart)
#password_encryption = on
#db_user_namespace = off

# - Kerberos -
#krb_server_keyfile = ''        # (change requires restart)
#krb_srvname = 'postgres'        # (change requires restart)
#krb_server_hostname = ''        # empty string matches any keytab entry
                    # (change requires restart)
#krb_caseins_users = off        # (change requires restart)

# - 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 = 32MB            # min 128kB or max_connections*16kB
                    # (change requires restart)
#temp_buffers = 8MB            # min 800kB
#max_prepared_transactions = 5        # can be 0 or more
                    # (change requires restart)
# Note: increasing max_prepared_transactions costs ~600 bytes of shared memory
# per transaction slot, plus lock space (see max_locks_per_transaction).
#work_mem = 1MB                # min 64kB
#maintenance_work_mem = 16MB        # min 1MB
#max_stack_depth = 2MB            # min 100kB

# - Free Space Map -

#max_fsm_pages = 204800            # min max_fsm_relations*16, 6 bytes each
                    # (change requires restart)
#max_fsm_relations = 1000        # min 100, ~70 bytes each
                    # (change requires restart)

# - Kernel Resource Usage -

#max_files_per_process = 1000        # min 25
                    # (change requires restart)
#shared_preload_libraries = ''        # (change requires restart)

# - Background writer -

#bgwriter_delay = 200ms            # 10-10000ms between rounds
#bgwriter_lru_percent = 1.0        # 0-100% of LRU buffers scanned/round
#bgwriter_lru_maxpages = 5        # 0-1000 buffers max written/round
#bgwriter_all_percent = 0.333        # 0-100% of all buffers scanned/round
#bgwriter_all_maxpages = 5        # 0-1000 buffers max written/round


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

# - Settings -

#fsync = on                # turns forced synchronization on or off
#wal_sync_method = fsync        # the default is the first option
                    # supported by the operating system:
                    #   open_datasync
                    #   fdatasync
                    #   fsync
                    #   fsync_writethrough
                    #   open_sync
#full_page_writes = on            # recover from partial page writes
#wal_buffers = 64kB            # min 32kB
                    # (change requires restart)
#commit_delay = 0            # range 0-100000, in microseconds
#commit_siblings = 5            # range 1-1000

# - Checkpoints -

#checkpoint_segments = 3        # in logfile segments, min 1, 16MB each
#checkpoint_timeout = 5min        # range 30s-1h
#checkpoint_warning = 30s        # 0 is off

# - Archiving -

#archive_command = ''        # command to use to archive a logfile segment
#archive_timeout = 0        # force a logfile segment switch after this
                # many seconds; 0 is off

#---------------------------------------------------------------------------
# VACUUM AND AUTOVACUUM
#---------------------------------------------------------------------------

# - General -

#vacuum_freeze_min_age = 100000000

# - Cost-Based Vacuum Delay -

#vacuum_cost_delay = 0            # 0-1000 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        # 0-10000 credits

# - Autovacuum -

#autovacuum = on            # enable autovacuum subprocess?
                    # 'on' requires stats_start_collector
                    # and stats_row_level to also be on
#autovacuum_max_workers = 3        # max # of autovacuum subprocesses
#autovacuum_naptime = 1min        # time between autovacuum runs
#log_autovacuum = -1            # -1 is disabled, 0 logs all actions
                    # and their durations, > 0 logs only
                    # actions running at least N msec.
#autovacuum_vacuum_threshold = 500    # min # of tuple updates before
                    # vacuum
#autovacuum_analyze_threshold = 250    # min # of tuple updates before
                    # analyze
#autovacuum_vacuum_scale_factor = 0.2    # fraction of rel size before
                    # vacuum
#autovacuum_analyze_scale_factor = 0.1    # fraction of rel size before
                    # analyze
#autovacuum_freeze_max_age = 200000000    # maximum XID age before forced vacuum
                    # (change requires restart)
#autovacuum_vacuum_cost_delay = -1    # default vacuum cost delay for
                    # autovacuum, -1 means use
                    # vacuum_cost_delay
#autovacuum_vacuum_cost_limit = -1    # default vacuum cost limit for
                    # autovacuum, -1 means use
                    # vacuum_cost_limit

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

# - Planner Method Configuration -

#enable_bitmapscan = on
#enable_hashagg = on
#enable_hashjoin = on
#enable_indexscan = 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
#effective_cache_size = 128MB

# - 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

# - Other Planner Options -

#default_statistics_target = 10        # range 1-1000
#constraint_exclusion = off
#from_collapse_limit = 8
#join_collapse_limit = 8        # 1 disables collapsing of explicit
                    # JOINs
#explain_pretty_print = on


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

# - Where to Log -

#log_destination = 'stderr'        # Valid values are combinations of
                    # stderr, syslog and eventlog,
                    # depending on platform.

# This is used when logging to stderr:
#redirect_stderr = off            # Enable capturing of stderr into log
                    # files
                    # (change requires restart)

# These are only used if redirect_stderr is on:
#log_directory = 'pg_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_truncate_on_rotation = off     # Truncate rather than appending to files
                    # of the same name.
#log_rotation_age = 1d            # Automatic rotation of logfiles will
                    # happen after that time.  0 to
                    # disable.
#log_rotation_size = 10MB        # Automatic rotation of logfiles will
                    # happen after that much log
                    # output.  0 to disable.

# These are relevant when logging to syslog:
#syslog_facility = 'LOCAL0'
#syslog_ident = 'postgres'


# - 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 = notice        # Values in order of decreasing detail:
                    #   debug5, debug4, debug3, debug2,
                    #   debug1, info, notice, warning,
                    #   error, log, fatal, panic
#log_error_verbosity = default        # terse, default, or verbose messages
#log_min_error_statement = error    # Values in order of decreasing detail:
                    #   debug5, debug4, debug3, debug2,
                    #   debug1, info, notice, warning,
                    #   error, log, fatal, panic (off)
#log_min_duration_statement = -1    # -1 is disabled, 0 logs all statements
                    # and their durations, > 0 logs only
                    # statements running at least N msec.
#silent_mode = off            # DO NOT USE without syslog or
                    # redirect_stderr

# - What to Log -

#debug_print_parse = off
#debug_print_rewritten = off
#debug_print_plan = off
#debug_pretty_print = off
#log_connections = off
#log_disconnections = off
#log_duration = off
#log_line_prefix = ''            # Special values:
                    #   %u = user name
                    #   %d = database name
                    #   %r = remote host and port
                    #   %h = remote host
                    #   %p = PID
                    #   %t = timestamp (no milliseconds)
                    #   %m = timestamp with milliseconds
                    #   %i = command tag
                    #   %c = session id
                    #   %l = session line number
                    #   %s = session start timestamp
                    #   %x = transaction id
                    #   %q = stop here in non-session
                    #        processes
                    #   %% = '%'
                    # e.g. '<%u%%%d> '
#log_statement = 'none'            # none, ddl, mod, all
#log_hostname = off
#log_lock_waits = off            # Log lock waits longer than deadlock_timeout
#log_temp_files = -1            # Log temporary files equal or larger
                    # than the specified number of kilobytes.
                    # -1 disables;  0 logs all temp files

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

# - Query/Index Statistics Collector -

#stats_command_string = on
#update_process_title = on

#stats_start_collector = on        # needed for block or row stats
                    # (change requires restart)
#stats_block_level = off
#stats_row_level = on
#stats_reset_on_server_start = off    # (change requires restart)


# - Statistics Monitoring -

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

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

# - Statement Behavior -

#search_path = '"$user",public'        # schema names
#default_tablespace = ''        # a tablespace name, '' uses
                    # the default
#default_transaction_isolation = 'read committed'
#default_transaction_read_only = off
#statement_timeout = 0            # 0 is disabled

# - Locale and Formatting -

#datestyle = 'iso, mdy'
#timezone = unknown            # actually, defaults to TZ
                    # environment setting
#timezone_abbreviations = 'Default'     # select the set of available timezone
                    # abbreviations. Currently, there are
                    #   Default
                    #   Australia
                    #   India
                    # However you can also create your own
                    # file in share/timezonesets/.
#extra_float_digits = 0            # min -15, max 2
#client_encoding = sql_ascii        # actually, defaults to database
                    # encoding

# These settings are initialized by initdb -- they might 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

# - Libraries -
#dynamic_library_path = '$libdir'
#local_preload_libraries = ''

# - XML -
#xmlbinary = 'base64'
#xmloption = 'content'

# - Other Defaults -

#check_function_bodies = on
#session_replication_role = "origin"

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

#deadlock_timeout = 1s
#max_locks_per_transaction = 64        # min 10
                    # (change requires restart)
# Note: each lock table slot uses ~270 bytes of shared memory, and there are
# max_locks_per_transaction * (max_connections + max_prepared_transactions)
# lock table slots.


#---------------------------------------------------------------------------
# VERSION/PLATFORM COMPATIBILITY
#---------------------------------------------------------------------------

# - Previous Postgres Versions -

#add_missing_from = off
#array_nulls = on
#backslash_quote = safe_encoding    # on, off, or safe_encoding
#default_with_oids = off
#escape_string_warning = on
#sql_inheritance = on
#regex_flavor = advanced        # advanced, extended, or basic
#standard_conforming_strings = off

# - Other Platforms & Clients -

#transform_null_equals = off


#---------------------------------------------------------------------------
# CUSTOMIZED OPTIONS
#---------------------------------------------------------------------------

#custom_variable_classes = ''        # list of custom variable class names