Re: Almost infinite query -> Different Query Plan when changing where clause value
От | lionel duboeuf |
---|---|
Тема | Re: Almost infinite query -> Different Query Plan when changing where clause value |
Дата | |
Msg-id | 4B75BADE.9030906@boozter.com обсуждение исходный текст |
Ответ на | Re: Almost infinite query -> Different Query Plan when changing where clause value ("Kevin Grittner" <Kevin.Grittner@wicourts.gov>) |
Ответы |
Re: Almost infinite query -> Different Query Plan
when changing where clause value
("Kevin Grittner" <Kevin.Grittner@wicourts.gov>)
|
Список | pgsql-performance |
Thanks kevin for your answer. Here is some additionnal informations attached as files. regards. Lionel Kevin Grittner a écrit : > lionel duboeuf <lionel.duboeuf@boozter.com> wrote: > > >> Some informations: >> The following problem has been detected on >> Postgresql 8.3 and 8.4. on System linux or windows >> Default AutoVacuum daemon working >> One pg_dump every day >> This happens sometimes and i don't see what can be the cause. >> A manual Vacuum Analyse repair that problem. >> > > It's good to know that the issue has been observed in more than one > release or on more than one platform, but it's also useful to get a > bit more information about one particular occurrence. Please read > this: > > http://wiki.postgresql.org/wiki/SlowQueryQuestions > > In particular, knowing such things as your postgresql.conf settings, > the disk configuration, how much RAM the machine has, etc. can allow > us to provide more useful advice. > > Please run these as EXPLAIN ANALYZE (or at least whatever you can > get to finish that way) instead of just EXPLAIN. If you can let the > slow one run through EXPLAIN ANALYZE overnight or on a test machine > so that it can complete, it will give us a lot more with which to > work. Please attach wide output (like that from EXPLAIN) as a text > attachment, to prevent wrapping which makes it hard to read. > > -Kevin > processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Core(TM)2 Duo CPU T7500 @ 2.20GHz stepping : 11 cpu MHz : 2201.000 cache size : 4096 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 2 apicid : 0 initial apicid : 0 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ssht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm lahf_lm idatpr_shadow vnmi flexpriority bogomips : 4389.59 clflush size : 64 power management: processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Core(TM)2 Duo CPU T7500 @ 2.20GHz stepping : 11 cpu MHz : 2201.000 cache size : 4096 KB physical id : 0 siblings : 2 core id : 1 cpu cores : 2 apicid : 1 initial apicid : 1 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ssht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm lahf_lm idatpr_shadow vnmi flexpriority bogomips : 4388.96 clflush size : 64 power management: QUERY PLAN Nested Loop (cost=58.71..1512.50 rows=1 width=16) (actual time=1.849..535681.136 rows=14 loops=1) -> Nested Loop (cost=58.71..1506.60 rows=1 width=20) (actual time=1.839..535680.377 rows=14 loops=1) Join Filter: (link0_.element_source = blocks9_.element_seqnum) -> Nested Loop (cost=58.71..1498.29 rows=1 width=32) (actual time=1.819..535337.910 rows=6534 loops=1) -> Nested Loop (cost=58.71..1497.14 rows=1 width=28) (actual time=1.811..535246.825 rows=6534 loops=1) -> Nested Loop (cost=58.71..1488.83 rows=1 width=36) (actual time=1.800..535160.718 rows=6534 loops=1) -> Nested Loop (cost=58.71..1484.40 rows=1 width=28) (actual time=1.772..535042.549 rows=6534loops=1) -> Nested Loop (cost=13.20..1434.87 rows=1 width=16) (actual time=1.398..8327.567 rows=122850loops=1) -> Nested Loop (cost=13.20..1428.97 rows=1 width=20) (actual time=1.387..1911.520rows=122850 loops=1) -> Nested Loop (cost=13.20..1427.83 rows=1 width=24) (actual time=1.374..517.662rows=122850 loops=1) -> Nested Loop (cost=0.00..16.63 rows=1 width=16) (actual time=0.085..0.409rows=15 loops=1) -> Index Scan using fki_element_block_block on element_block blocks7_ (cost=0.00..8.30 rows=1 width=8) (actual time=0.045..0.082 rows=15 loops=1) Index Cond: (block_seqnum = 5) -> Index Scan using pk_user_element on user_element users3_ (cost=0.00..8.33rows=1 width=8) (actual time=0.012..0.015 rows=1 loops=15) Index Cond: ((users3_.user_seqnum = 10) AND (users3_.element_seqnum= blocks7_.element_seqnum)) -> Bitmap Heap Scan on user_element users5_ (cost=13.20..1404.85 rows=634width=8) (actual time=1.091..12.478 rows=8190 loops=15) Recheck Cond: (users5_.user_seqnum = 10) -> Bitmap Index Scan on fki_user_element_user (cost=0.00..13.05rows=634 width=0) (actual time=1.062..1.062 rows=8194 loops=15) Index Cond: (users5_.user_seqnum = 10) -> Seq Scan on block block8_ (cost=0.00..1.14 rows=1 width=4) (actual time=0.004..0.005rows=1 loops=122850) Filter: (block8_.block_seqnum = 5) -> Seq Scan on "user" user4_ (cost=0.00..5.89 rows=1 width=4) (actual time=0.005..0.047rows=1 loops=122850) Filter: (user4_.user_seqnum = 10) -> Bitmap Heap Scan on link link0_ (cost=45.50..49.51 rows=1 width=12) (actual time=4.283..4.283rows=0 loops=122850) Recheck Cond: ((link0_.element_source = users5_.element_seqnum) AND (link0_.element_target= users3_.element_seqnum)) Filter: (link0_.link_sup_date IS NULL) -> BitmapAnd (cost=45.50..45.50 rows=1 width=0) (actual time=4.280..4.280 rows=0loops=122850) -> Bitmap Index Scan on element_source_fk (cost=0.00..4.61 rows=21 width=0)(actual time=0.007..0.007 rows=6 loops=122850) Index Cond: (link0_.element_source = users5_.element_seqnum) -> Bitmap Index Scan on element_target_fk (cost=0.00..40.12 rows=2089 width=0)(actual time=4.719..4.719 rows=33814 loops=110880) Index Cond: (link0_.element_target = users3_.element_seqnum) -> Index Scan using pk_element on element element2_ (cost=0.00..4.41 rows=1 width=8) (actualtime=0.009..0.011 rows=1 loops=6534) Index Cond: (element2_.element_seqnum = link0_.element_source) -> Index Scan using pk_element on element element1_ (cost=0.00..8.31 rows=1 width=4) (actual time=0.006..0.007rows=1 loops=6534) Index Cond: (element1_.element_seqnum = link0_.element_target) -> Seq Scan on block block10_ (cost=0.00..1.14 rows=1 width=4) (actual time=0.005..0.007 rows=1 loops=6534) Filter: (block10_.block_seqnum = 5) -> Index Scan using fki_element_block_block on element_block blocks9_ (cost=0.00..8.30 rows=1 width=8) (actualtime=0.007..0.030 rows=15 loops=6534) Index Cond: (blocks9_.block_seqnum = 5) -> Seq Scan on "user" user6_ (cost=0.00..5.89 rows=1 width=4) (actual time=0.006..0.048 rows=1 loops=14) Filter: (user6_.user_seqnum = 10) Total runtime: 535681.414 ms MemTotal: 3087448 kB MemFree: 2355500 kB Buffers: 22212 kB Cached: 396520 kB SwapCached: 0 kB Active: 387472 kB Inactive: 289388 kB Active(anon): 313808 kB Inactive(anon): 0 kB Active(file): 73664 kB Inactive(file): 289388 kB Unevictable: 0 kB Mlocked: 0 kB HighTotal: 2226696 kB HighFree: 1560912 kB LowTotal: 860752 kB LowFree: 794588 kB SwapTotal: 0 kB SwapFree: 0 kB Dirty: 6216 kB Writeback: 0 kB AnonPages: 258144 kB Mapped: 127688 kB Slab: 28196 kB SReclaimable: 14624 kB SUnreclaim: 13572 kB PageTables: 5272 kB NFS_Unstable: 0 kB Bounce: 0 kB WritebackTmp: 0 kB CommitLimit: 1543724 kB Committed_AS: 913152 kB VmallocTotal: 122880 kB VmallocUsed: 11192 kB VmallocChunk: 88472 kB HugePages_Total: 0 HugePages_Free: 0 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 4096 kB DirectMap4k: 16376 kB DirectMap4M: 892928 kB # ----------------------------- # 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 paramters can be changed at run time # with the "SET" SQL command. # # Memory units: kB = kilobytes MB = megabytes GB = gigabytes # Time units: ms = milliseconds s = seconds 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/8.3/main' # use data in another directory # (change requires restart) hba_file = '/etc/postgresql/8.3/main/pg_hba.conf' # host-based authentication file # (change requires restart) ident_file = '/etc/postgresql/8.3/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/8.3-main.pid' # 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 = '/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) #password_encryption = on #db_user_namespace = off # Kerberos and GSSAPI #krb_server_keyfile = '' # (change requires restart) #krb_srvname = 'postgres' # (change requires restart, Kerberos only) #krb_server_hostname = '' # empty string matches any keytab entry # (change requires restart, Kerberos only) #krb_caseins_users = off # (change requires restart) #krb_realm = '' # (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 = 24MB # 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 = 153600 # 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) # - 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 # 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 #------------------------------------------------------------------------------ # WRITE AHEAD LOG #------------------------------------------------------------------------------ # - Settings - #fsync = on # 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 # fsync # fsync_writethrough # open_sync #full_page_writes = on # recover from partial page writes #wal_buffers = 64kB # min 32kB # (change requires restart) #wal_writer_delay = 200ms # 1-10000 milliseconds #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_completion_target = 0.5 # checkpoint target duration, 0.0 - 1.0 #checkpoint_warning = 30s # 0 is off # - 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 # time; 0 is off #------------------------------------------------------------------------------ # 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 # 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 = '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 # 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 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 (effectively off) log_min_duration_statement = 100 # -1 is disabled, 0 logs all statements # and their durations, > 0 logs only # statements running at least this time. #silent_mode = off # DO NOT USE without syslog or # logging_collector # (change requires restart) # - What to Log - #debug_print_parse = off #debug_print_rewritten = off #debug_print_plan = off #debug_pretty_print = off #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 specified size; # -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 #update_process_title = on # - 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 that time. #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 = 20 # 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 #------------------------------------------------------------------------------ # CLIENT CONNECTION DEFAULTS #------------------------------------------------------------------------------ # - Statement Behavior - #search_path = '"$user",public' # schema names #default_tablespace = '' # a tablespace name, '' uses the default #temp_tablespaces = '' # a list of tablespace names, '' uses # only default tablespace #check_function_bodies = on #default_transaction_isolation = 'read committed' #default_transaction_read_only = off #session_replication_role = 'origin' #statement_timeout = 0 # 0 is disabled #vacuum_freeze_min_age = 100000000 #xmlbinary = 'base64' #xmloption = 'content' # - Locale and Formatting - datestyle = 'iso, dmy' #timezone = unknown # actually, defaults to TZ environment # setting #timezone_abbreviations = 'Default' # Select the set of available time zone # abbreviations. Currently, there are # Default # Australia # India # You can create your own file in # share/timezonesets/. #extra_float_digits = 0 # min -15, max 2 #client_encoding = sql_ascii # actually, defaults to database # encoding # These settings are initialized by initdb, but they can be changed. lc_messages = 'fr_FR.UTF-8' # locale for system error message # strings lc_monetary = 'fr_FR.UTF-8' # locale for monetary formatting lc_numeric = 'fr_FR.UTF-8' # locale for number formatting lc_time = 'fr_FR.UTF-8' # locale for time formatting # default configuration for text search default_text_search_config = 'pg_catalog.french' # - Other Defaults - #explain_pretty_print = on #dynamic_library_path = '$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
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Сообщение: Re: Almost infinite query -> Different Query Plan when changing where clause value