postgresql.conf question - 500 points

# 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.
#
# Any option can also be given as a command line switch to the
# postmaster, e.g. 'postmaster -c log_connections=on'. Some options
# can be changed at run-time with the 'SET' SQL command.
#
# This file is read on postmaster startup and when the postmaster
# receives a SIGHUP. If you edit the file on a running system, you have
# to SIGHUP the postmaster for the changes to take effect, or use
# "pg_ctl reload".
 
 
#========================================================================
 
 
#
#       Connection Parameters
#
#tcpip_socket = false
#ssl = false
 
#max_connections = 32
#superuser_reserved_connections = 2
 
#port = 5432
#hostname_lookup = false
#show_source_port = false
 
#unix_socket_directory = ''
#unix_socket_group = ''
#unix_socket_permissions = 0777 # octal
 
#virtual_host = ''
 
#krb_server_keyfile = ''
 
 
#
#       Shared Memory Size
#
#shared_buffers = 64            # min max_connections*2 or 16, 8KB each
#max_fsm_relations = 1000       # min 10, fsm is free space map, ~40 bytes
#max_fsm_pages = 10000          # min 1000, fsm is free space map, ~6 bytes
#max_locks_per_transaction = 64 # min 10
#wal_buffers = 8                # min 4, typically 8KB each
 
#
#       Non-shared Memory Sizes
#
#sort_mem = 1024                # min 64, size in KB
#vacuum_mem = 8192              # min 1024, size in KB
 
 
#
#       Write-ahead log (WAL)
#
#checkpoint_segments = 3        # in logfile segments, min 1, 16MB each
#checkpoint_timeout = 300       # range 30-3600, in seconds
#
#commit_delay = 0               # range 0-100000, in microseconds
#commit_siblings = 5            # range 1-1000
#
#fsync = true
#wal_sync_method = fsync        # the default varies across platforms:
#                               # fsync, fdatasync, open_sync, or open_datasync
#wal_debug = 0                  # range 0-16
 
 
#
#       Optimizer Parameters
#
#enable_seqscan = true
#enable_indexscan = true
#enable_tidscan = true
#enable_sort = true
#enable_nestloop = true
#enable_mergejoin = true
#enable_hashjoin = true
 
#effective_cache_size = 1000    # typically 8KB each
#random_page_cost = 4           # units are one sequential page fetch cost
#cpu_tuple_cost = 0.01          # (same)
#cpu_index_tuple_cost = 0.001   # (same)
#cpu_operator_cost = 0.0025     # (same)
 
#from_collapse_limit = 8
#join_collapse_limit = 8        # 1 disables collapsing of explicit JOINs
 
#default_statistics_target = 10 # range 1-1000
 
#
#       GEQO Optimizer Parameters
#
#geqo = true
#geqo_selection_bias = 2.0      # range 1.5-2.0
#geqo_threshold = 11
#geqo_pool_size = 0             # default based on tables in statement,
                                # range 128-1024
#geqo_effort = 1
#geqo_generations = 0
#geqo_random_seed = -1          # auto-compute seed
 
 
#
#       Message display
#
#server_min_messages = notice   # Values, in order of decreasing detail:
                                #   debug5, debug4, debug3, debug2, debug1,
                                #   info, notice, warning, error, log, fatal,
                                #   panic
#client_min_messages = notice   # Values, in order of decreasing detail:
                                #   debug5, debug4, debug3, debug2, debug1,
                                #   log, info, notice, warning, error
#silent_mode = false
 
#log_connections = false
#log_pid = false
#log_statement = false
#log_duration = false
#log_timestamp = false
 
#log_min_error_statement = panic # Values in order of increasing severity:
                                 #   debug5, debug4, debug3, debug2, debug1,
                                 #   info, notice, warning, error, panic(off)
 
#debug_print_parse = false
#debug_print_rewritten = false
#debug_print_plan = false
#debug_pretty_print = false
 
#explain_pretty_print = true
 
# requires USE_ASSERT_CHECKING
#debug_assertions = true
 
 
#
#       Syslog
#
#syslog = 0                     # range 0-2
#syslog_facility = 'LOCAL0'
#syslog_ident = 'postgres'
syslog=2
 
#
#       Statistics
#
#show_parser_stats = false
#show_planner_stats = false
#show_executor_stats = false
#show_statement_stats = false
 
# requires BTREE_BUILD_STATS
#show_btree_build_stats = false
 
 
#
#       Access statistics collection
#
#stats_start_collector = true
#stats_reset_on_server_start = true
#stats_command_string = false
#stats_row_level = false
#stats_block_level = false
 
 
#
#       Lock Tracing
#
#trace_notify = false
 
# requires LOCK_DEBUG
#trace_locks = false
#trace_userlocks = false
#trace_lwlocks = false
#debug_deadlocks = false
#trace_lock_oidmin = 16384
#trace_lock_table = 0
 
 
#
#       Misc
#
#autocommit = true
#dynamic_library_path = '$libdir'
#search_path = '$user,public'
#datestyle = 'iso, us'
#timezone = unknown             # actually, defaults to TZ environment setting
#australian_timezones = false
#client_encoding = sql_ascii    # actually, defaults to database encoding
#authentication_timeout = 60    # 1-600, in seconds
#deadlock_timeout = 1000        # in milliseconds
#default_transaction_isolation = 'read committed'
#max_expr_depth = 10000         # min 10
#max_files_per_process = 1000   # min 25
#password_encryption = true
#sql_inheritance = true
#transform_null_equals = false
#statement_timeout = 0          # 0 is disabled, in milliseconds
#db_user_namespace = false
#backslash_quote = safe_encoding        # on, off, or safe_encoding
 
 
 
#
#       Locale settings
#
# (initialized by initdb -- may be changed)
LC_MESSAGES = 'en_US.UTF-8'
LC_MONETARY = 'en_US.UTF-8'
LC_NUMERIC = 'en_US.UTF-8'
LC_TIME = 'en_US.UTF-8'
shared_buffers = 512
tcpip_socket = true
port = 5432
syslog = 2