[postgis-users] Query slow down, never completes

Andreas Forø Tollefsen andreasft at gmail.com
Wed Oct 12 00:59:27 PDT 2011


Postgresql.conf

  # -----------------------------
# 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, or use "pg_ctl reload".  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
#                                                   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 = '/var/lib/postgresql/8.4/main'		# use data in another directory
					# (change requires restart)
hba_file = '/etc/postgresql/8.4/main/pg_hba.conf'	# host-based
authentication file
					# (change requires restart)
ident_file = '/etc/postgresql/8.4/main/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 = '/var/run/postgresql/8.4-main.pid'		# write an
extra PID file
					# (change requires restart)


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

# - Connection Settings -

listen_addresses = '*'		# 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 = 10			# (change requires restart)
# Note:  Increasing max_connections costs ~400 bytes of shared memory per
# connection slot, plus lock space (see max_locks_per_transaction).
#superuser_reserved_connections = 3	# (change requires restart)
unix_socket_directory = '/var/run/postgresql'		# (change requires restart)
#unix_socket_group = ''			# (change requires restart)
#unix_socket_permissions = 0777		# begin with 0 to use octal notation
					# (change requires restart)
#bonjour_name = ''			# defaults to the computer name
					# (change requires restart)

# - Security and Authentication -

#authentication_timeout = 1min		# 1s-600s
ssl = true				# (change requires restart)
#ssl_ciphers = 'ALL:!ADH:!LOW:!EXP:!MD5:@STRENGTH'	# allowed SSL ciphers
					# (change requires restart)
#ssl_renegotiation_limit = 512MB	# amount of data between renegotiations
#password_encryption = on
#db_user_namespace = off

# Kerberos and GSSAPI
#krb_server_keyfile = ''
#krb_srvname = 'postgres'		# (Kerberos only)
#krb_caseins_users = off

# - 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 = 2200MB			# min 128kB
					# (change requires restart)
temp_buffers = 256MB			# min 800kB
#max_prepared_transactions = 0		# zero disables the feature
					# (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).
# It is not advisable to set max_prepared_transactions nonzero unless you
# actively intend to use prepared transactions.
work_mem = 512MB			# min 64kB
maintenance_work_mem = 128MB		# min 1MB
#max_stack_depth = 2MB			# min 100kB

# - Kernel Resource Usage -

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

# - Cost-Based Vacuum Delay -

#vacuum_cost_delay = 0ms		# 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 multipler on buffers scanned/round

# - Asynchronous Behavior -

#effective_io_concurrency = 1		# 1-1000. 0 disables prefetching


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

# - Settings -

fsync = off				# turns forced synchronization on or off
#synchronous_commit = on		# immediate fsync at commit
#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_buffers = 640kB			# min 32kB
					# (change requires restart)
#wal_writer_delay = 200ms		# 1-10000 milliseconds

commit_delay = 20			# range 0-100000, in microseconds
commit_siblings = 200			# range 1-1000

# - Checkpoints -

checkpoint_segments = 10		# in logfile segments, min 1, 16MB each
checkpoint_timeout = 30s			# range 30s-1h
checkpoint_completion_target = 0.5	# checkpoint target duration, 0.0 - 1.0
#checkpoint_warning = 30s		# 0 disables

# - Archiving -

#archive_mode = off		# allows archiving to be done
				# (change requires restart)
#archive_command = ''		# command to use to archive a logfile segment
#archive_timeout = 0		# force a logfile segment switch after this
				# number of seconds; 0 disables


#------------------------------------------------------------------------------
# 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 = 4096MB

# - 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 = 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


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

# - Where to Log -

log_destination = 'stderr'		# 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 = '/var/log/postgresql'		# 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		# If on, an existing log file of 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'

#silent_mode = off			# Run server silently.
					# DO NOT USE without syslog or
					# logging_collector
					# (change requires restart)


# - 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_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 (effectively off)

#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_hostname = off
log_line_prefix = '%t '			# special values:
					#   %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
					#   %i = command tag
					#   %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 = off			# log lock waits >= deadlock_timeout
#log_statement = 'none'			# none, ddl, mod, all
#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 = unknown			# actually, defaults to TZ environment
					# setting


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

# - Query/Index Statistics Collector -

#track_activities = on
#track_counts = on
#track_functions = none			# none, pl, all
#track_activity_query_size = 1024
#update_process_title = on
#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 = -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
					# (change requires restart)
#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
#session_replication_role = 'origin'
#statement_timeout = 0			# in milliseconds, 0 is disabled
#vacuum_freeze_min_age = 50000000
#vacuum_freeze_table_age = 150000000
#xmlbinary = 'base64'
#xmloption = 'content'

# - Locale and Formatting -

datestyle = 'iso, mdy'
#intervalstyle = 'postgres'
#timezone = unknown			# actually, defaults to TZ environment
					# setting
#timezone_abbreviations = 'Default'     # Select the set of available time zone
					# abbreviations.  Currently, there are
					#   Default
					#   Australia
					#   India
					# You can 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, 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'

# - Other Defaults -

#dynamic_library_path = '$libdir'
#local_preload_libraries = ''


#------------------------------------------------------------------------------
# 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 PostgreSQL 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
#regex_flavor = advanced		# advanced, extended, or basic
#sql_inheritance = on
#standard_conforming_strings = off
#synchronize_seqscans = on

# - Other Platforms and Clients -

#transform_null_equals = off


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

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


2011/10/12 Andreas Forø Tollefsen <andreasft at gmail.com>

> Yes, I did a version of the query where i terminated the connection in the
> loop after one year, and then reconnected to the server for each year in the
> query.
> This did not change anything, and the query still halted on the same year.
> Like this:
> # For each year calculate the distance to border and insert into the
> borddist table
> yearlist = range(1946, 2009, 1)
> for x in yearlist:
>     db1 = psycopg2.connect("host=192.168.1.186 dbname=priogrid
> user=postgres password=postgres")
>     cur = db1.cursor()
>     print str(time.ctime())+ " Creating borddist for year "+str(x)+"."
>     cur.execute("INSERT INTO borddist(gid, gwcode, gridyear, borddist)
> SELECT a.gid, a.gwcode, "+str(x)+", MIN(ST_Distance(ST_Transform(a.centroid,
> 954010), ST_Transform(b.geom, 954010)))/1000 AS borddist \n" \
>                 "FROM priogridall_geom a, cshapes b, cshapes c WHERE
> a.gwcode != b.gwcode AND b.gwsyear <= "+str(x)+" AND b.gweyear >= "+str(x)+"
> \n" \
>                 "and a.gwcode = c.gwcode and st_intersects(b.geom, c.geom)
> AND a.gridyear = "+str(x)+" GROUP BY a.gid, a.gwcode;")
>     db1.commit()
>     cur.close()
>     db1.close()
> db1.commit()
> print str(time.ctime())+ " Done"
> cur.close()
> db1.close()
>
> I also followed your suggestion to not write any data. Just do a select,
> without any select into or insert into.
> The same problem occurred.
> Script:
>     cur.execute("SELECT a.gid, a.gwcode, "+str(x)+", "\
>                 "MIN(ST_Distance(a.centroid, b.geom)) "\
>                 "FROM priogridall_geom a, cshapes b, cshapes c WHERE
> a.gwcode != b.gwcode AND b.gwsyear <= "+str(x)+" AND b.gweyear >= "+str(x)+"
> "\
>                 "AND a.gwcode = c.gwcode and ST_Intersects(b.geom, c.geom)
> AND a.gridyear = "+str(x)+" GROUP BY a.gid, a.gwcode;")
>     db1.commit()
>
> Thank you very much for looking into this. I have used over two weeks to
> try to figure this out.
> The only thing i can do is to run the script for 1/2 the years, then
> restart the server "service postgresql restart" and then run it for the next
> 1/2.
>
> Some memory and cpu information.
>
> Here is how it looks in free -m and top when the script have halted.
>              total       used       free     shared    buffers     cached
> Mem:     5977       5371        605          0        139       4735
> -/+ buffers/cache:   495       5481
> Swap:    6075          1       6074
>
> top - 09:51:07 up 1 day, 18:44,  2 users,  load average: 1.88, 1.32, 1.20
> Tasks: 165 total,   2 running, 162 sleeping,   0 stopped,   1 zombie
> Cpu(s): 53.2%us,  1.3%sy,  0.0%ni, 45.5%id,  0.0%wa,  0.0%hi,  0.0%si,
>  0.0%st
> Mem:   6120848k total,  5505868k used,   614980k free,   143004k buffers
> Swap:  6221820k total,     1468k used,  6220352k free,  4849556k cached
>
>   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
>
>
>  7810 postgres  20   0 2264m 1.0g 1.0g R  100 18.0 988:09.39 postgres
>
>
>  1417 andreas   20   0  163m  39m  14m S    3  0.7   3:27.13 compiz
>
>
>   907 root      20   0 57092  34m  10m S    2  0.6   1:48.73 Xorg
>
>
>  7088 andreas   20   0 93012  15m  10m S    2  0.3   0:02.80 gnome-terminal
>
>
> 10772 andreas   20   0  204m  96m  23m S    2  1.6   0:19.88
> chromium-browse
>
>  1525 andreas   20   0  100m  15m 9548 S    1  0.3   5:11.16
> unity-panel-ser
>
> 10675 andreas   20   0  308m  50m  29m S    1  0.8   0:07.55
> chromium-browse
>
>  1088 root      20   0  9420 1632  964 S    0  0.0   0:07.01 nmbd
>
>
>  1389 andreas   20   0  5552 2740  700 S    0  0.0   1:17.77 dbus-daemon
>
>
> 10825 andreas   20   0 35836  19m 6276 S    0  0.3   0:02.94 idle-python2.6
>
>
>     1 root      20   0  3040 1780 1220 S    0  0.0   0:02.16 init
>
>
>     2 root      20   0     0    0    0 S    0  0.0   0:00.01 kthreadd
>
>
>     3 root      20   0     0    0    0 S    0  0.0   0:07.21 ksoftirqd/0
>
>
>     6 root      RT   0     0    0    0 S    0  0.0   0:00.00 migration/0
>
>
>     7 root      RT   0     0    0    0 S    0  0.0   0:00.00 migration/1
>
>
>     9 root      20   0     0    0    0 S    0  0.0   0:03.00 ksoftirqd/1
>
>
>    11 root       0 -20     0    0    0 S    0  0.0   0:00.00 cpuset
>
>
> After i restart the postgresql service:
>              total       used       free     shared    buffers     cached
> Mem:     5977       4319       1657          0        139       3687
> -/+ buffers/cache:   492       5484
> Swap:         6075       1       6074
>
> top - 09:52:33 up 1 day, 18:46,  2 users,  load average: 1.42, 1.33, 1.22
> Tasks: 164 total,   1 running, 162 sleeping,   0 stopped,   1 zombie
> Cpu(s):  1.3%us,  0.3%sy,  0.0%ni, 98.3%id,  0.0%wa,  0.0%hi,  0.0%si,
>  0.0%st
> Mem:   6120848k total,  4430204k used,  1690644k free,   143092k buffers
> Swap:  6221820k total,     1468k used,  6220352k free,  3776880k cached
>
>   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
>
>
>   907 root      20   0 52996  30m 6728 S    1  0.5   1:49.78 Xorg
>
>
>  1417 andreas   20   0  163m  39m  14m S    1  0.7   3:28.43 compiz
>
>
>   194 root      20   0     0    0    0 S    0  0.0   0:48.68 usb-storage
>
>
>  1447 root      20   0  5564 1000  712 S    0  0.0   0:23.28 udisks-daemon
>
>
>  1525 andreas   20   0  100m  15m 9548 S    0  0.3   5:11.66
> unity-panel-ser
>
>  1583 andreas   20   0 33552  16m 8984 S    0  0.3   0:03.21 applet.py
>
>
>  7039 andreas   20   0 44240  23m 6304 S    0  0.4   0:04.51 idle-python2.6
>
>
>  7088 andreas   20   0 93264  15m  10m S    0  0.3   0:03.28 gnome-terminal
>
>
>     1 root      20   0  3040 1780 1220 S    0  0.0   0:02.16 init
>
>
>     2 root      20   0     0    0    0 S    0  0.0   0:00.01 kthreadd
>
>
>     3 root      20   0     0    0    0 S    0  0.0   0:07.21 ksoftirqd/0
>
>
>     6 root      RT   0     0    0    0 S    0  0.0   0:00.00 migration/0
>
>
>     7 root      RT   0     0    0    0 S    0  0.0   0:00.00 migration/1
>
>
>     9 root      20   0     0    0    0 S    0  0.0   0:03.00 ksoftirqd/1
>
>
>
> 2011/10/11 Sandro Santilli <strk at keybit.net>
>
>> On Tue, Oct 11, 2011 at 05:12:24PM +0200, Andreas Forø Tollefsen wrote:
>> > Hi Sandro,
>> >
>> > What i find strange is that it stops processing at different years on my
>> > desktop and my laptop. While my desktop stops processing at 1980, my
>> slower
>> > laptop goes on to 1991 before halting.
>> > I also tried with different postgresql.conf shared_buffers settings
>> without
>> > making any difference.
>> > Therefore it is hard to reproduce this for a single year. I can easily
>> > process 1980 or 1991 if just running the script for that year.
>>
>> But you mentioned you had stopped the backend and restarted for each year
>> ?
>> Does the problem still occur if you avoid writing any table (could be an
>> I/O
>> issue) ?
>>
>> --strk;
>>
>>  ()   Free GIS & Flash consultant/developer
>>  /\   http://strk.keybit.net/services.html
>> _______________________________________________
>> postgis-users mailing list
>> postgis-users at postgis.refractions.net
>> http://postgis.refractions.net/mailman/listinfo/postgis-users
>>
>
>
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