RES: select on 1milion register = 6s

От: Bruno Rodrigues Siqueira
Тема: RES: select on 1milion register = 6s
Дата: ,
Msg-id: 002b01c7d168$58b7c130$e900a8c0@brunolaptop
(см: обсуждение, исходный текст)
Ответ на: Re: select on 1milion register = 6s  (Hervé Piedvache)
Список: pgsql-performance

Скрыть дерево обсуждения

select on 1milion register = 6s  ("Bruno Rodrigues Siqueira", )
 Re: select on 1milion register = 6s  (Craig James, )
  RES: select on 1milion register = 6s  ("Bruno Rodrigues Siqueira", )
   Re: RES: select on 1milion register = 6s  (Ragnar, )
    RES: RES: select on 1milion register = 6s  ("Bruno Rodrigues Siqueira", )
    Re: RES: select on 1milion register = 6s  (Decibel!, )
     RES: RES: select on 1milion register = 6s  ("Bruno Rodrigues Siqueira", )
      Re: RES: RES: select on 1milion register = 6s  (Decibel!, )
     Re: RES: RES: select on 1milion register = 6s  (Decibel!, )
   Re: select on 1milion register = 6s  ("Scott Marlowe", )
    Re: select on 1milion register = 6s  (Alvaro Herrera, )
    Re: select on 1milion register = 6s  (Jan Dittmer, )
 Re: select on 1milion register = 6s  (Hervé Piedvache, )
  RES: select on 1milion register = 6s  ("Bruno Rodrigues Siqueira", )
  RES: select on 1milion register = 6s  ("Bruno Rodrigues Siqueira", )

Yes.



Look this... and please, tell me if you can help me...


Thanks

Query

EXPLAIN
ANALYZE
select
       to_char(data_encerramento,'mm/yyyy')  as opcoes_mes,
       to_char(data_encerramento,'yyyy-mm') as ordem from detalhamento_bas
where

to_char( data_encerramento ,'yyyy-mm')
between   '2006-12' and  '2007-01'

GROUP BY opcoes_mes, ordem
ORDER BY ordem DESC





    QUERY RESULT

QUERY PLAN
Sort  (cost=11449.37..11449.40 rows=119 width=8) (actual
time=14431.537..14431.538 rows=2 loops=1)
  Sort Key: to_char(data_encerramento, 'yyyy-mm'::text)
  ->  HashAggregate  (cost=11448.79..11448.96 rows=119 width=8) (actual
time=14431.521..14431.523 rows=2 loops=1)
        ->  Index Scan using detalhamento_bas_idx3003 on detalhamento_bas
(cost=0.00..11442.95 rows=11679 width=8) (actual time=0.135..12719.155
rows=2335819 loops=1)
              Index Cond: ((to_char(data_encerramento, 'yyyy-mm'::text) >=
'2006-12'::text) AND (to_char(data_encerramento, 'yyyy-mm'::text) <=
'2007-01'::text))
Total runtime: 14431.605 ms








    SERVER
           DELL PowerEdge 2950
          XEON Quad-Core 3.0Ghz
          4Gb RAM
          Linux CentOS 5.0 64-bits





     Postgres 8.1.4




     Postgresql.conf


# -----------------------------
# PostgreSQL configuration file
# -----------------------------
#
# This file consists of lines of the form:
#
#   name = value
#
# (The '=' is optional.) White space may be used. Comments are introduced #
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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 postmaster.
#
# 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". Some
settings, such as listen_addresses, require # a postmaster shutdown and
restart to take effect.


#---------------------------------------------------------------------------
# FILE LOCATIONS
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# 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
#hba_file = 'ConfigDir/pg_hba.conf'    # host-based authentication file
#ident_file = 'ConfigDir/pg_ident.conf'    # IDENT configuration file

# If external_pid_file is not explicitly set, no extra pid file is written.
#external_pid_file = '(none)'        # write an extra pid file


#---------------------------------------------------------------------------
# CONNECTIONS AND AUTHENTICATION
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# - Connection Settings -

listen_addresses = '*'        # what IP address(es) to listen on;
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#port = 5432 max_connections = 10 # note: increasing max_connections costs
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max_locks_per_transaction).  You # might also need to raise shared_buffers
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# Kerberos
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#krb_srvname = 'postgres'
#krb_server_hostname = ''        # empty string matches any keytab
entry
#krb_caseins_users = off

# - TCP Keepalives -
# see 'man 7 tcp' for details

#tcp_keepalives_idle = 0        # TCP_KEEPIDLE, in seconds;
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#tcp_keepalives_interval = 0        # TCP_KEEPINTVL, in seconds;
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#tcp_keepalives_count = 0        # TCP_KEEPCNT;
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#---------------------------------------------------------------------------
# RESOURCE USAGE (except WAL)
#---------------------------------------------------------------------------

# - Memory -

shared_buffers = 50000            # min 16 or max_connections*2, 8KB
each
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#max_prepared_transactions = 5        # can be 0 or more
# note: increasing max_prepared_transactions costs ~600 bytes of shared
memory # per transaction slot, plus lock space (see
max_locks_per_transaction).
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maintenance_work_mem = 4194304        # min 1024, size in KB
max_stack_depth = 2048            # min 100, size in KB

# - Free Space Map -

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each
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#preload_libraries = ''

# - Cost-Based Vacuum Delay -

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#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

# - Background writer -

bgwriter_delay = 200            # 10-10000 milliseconds between
rounds
bgwriter_lru_percent = 20.0        # 0-100% of LRU buffers
scanned/round
bgwriter_lru_maxpages = 100        # 0-1000 buffers max written/round
bgwriter_all_percent = 3        # 0-100% of all buffers
scanned/round
bgwriter_all_maxpages = 600        # 0-1000 buffers max written/round


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

# - Settings -

fsync = off                # turns forced synchronization on or
off
#wal_sync_method = fsync        # the default is the first option
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full_page_writes = off            # recover from partial page writes
wal_buffers = 2300            # min 4, 8KB each
commit_delay = 10            # range 0-100000, in microseconds
#commit_siblings = 5            # range 1-1000

# - Checkpoints -

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each
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logfile
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#---------------------------------------------------------------------------
# QUERY TUNING
#---------------------------------------------------------------------------

# - Planner Method Configuration -

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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 -

effective_cache_size = 41943040        # typically 8KB each
random_page_cost = 1            # units are one sequential page
fetch
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cpu_tuple_cost = 0.001            # (same)
cpu_index_tuple_cost = 0.0005        # (same)
cpu_operator_cost = 0.00025        # (same)

# - Genetic Query Optimizer -

#geqo = on
#geqo_threshold = 12
#geqo_effort = 5            # range 1-10
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# These are only used if redirect_stderr is on:
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PGDATA
log_filename = 'postgresql-%a.log'    # Log file name pattern.
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But
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is
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files
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will
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to
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will
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log
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# These are relevant when logging to syslog:
#syslog_facility = 'LOCAL0'
#syslog_ident = 'postgres'


# - When to Log -

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#log_error_verbosity = default        # terse, default, or verbose
messages

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severity:
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#log_duration = off
#log_line_prefix = ''            # Special values:
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                    #   %q = stop here in non-session
                    #        processes
                    #   %% = '%'
                    # e.g. '<%u%%%d> '
#log_statement = 'none'            # none, mod, ddl, all
#log_hostname = off


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

# - Statistics Monitoring -

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

# - Query/Index Statistics Collector -

stats_start_collector = off
#stats_command_string = off
#stats_block_level = off
#stats_row_level = off
#stats_reset_on_server_start = off


#---------------------------------------------------------------------------
# AUTOVACUUM PARAMETERS
#---------------------------------------------------------------------------

autovacuum = on            # enable autovacuum subprocess?
#autovacuum_naptime = 60        # time between autovacuum runs, in
secs
#autovacuum_vacuum_threshold = 1000    # min # of tuple updates before
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#autovacuum_analyze_threshold = 500    # min # of tuple updates before
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#autovacuum_analyze_scale_factor = 0.2    # fraction of rel size before
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#autovacuum_vacuum_cost_delay = -1    # default vacuum cost delay for
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#autovacuum_vacuum_cost_limit = -1    # default vacuum cost limit for
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                    # vacuum_cost_limit


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

# - Statement Behavior -

#search_path = '$user,public'        # schema names
#default_tablespace = ''        # a tablespace name, '' uses
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#check_function_bodies = on
default_transaction_isolation = 'read committed'
#default_transaction_read_only = off
#statement_timeout = 0            # 0 is disabled, in milliseconds

# - Locale and Formatting -

datestyle = 'iso, dmy'
#timezone = unknown            # actually, defaults to TZ
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#australian_timezones = off
#extra_float_digits = 0            # min -15, max 2
client_encoding = LATIN1        # actually, defaults to database
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# These settings are initialized by initdb -- they might be changed
lc_messages = 'pt_BR.ISO-8859-1'            # locale for system
error message
                    # strings
lc_monetary = 'pt_BR.ISO-8859-1'            # locale for
monetary formatting
lc_numeric = 'pt_BR.ISO-8859-1'            # locale for number
formatting
lc_time = 'pt_BR.ISO-8859-1'                # locale for time
formatting

# - Other Defaults -

#explain_pretty_print = on
#dynamic_library_path = '$libdir'


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

deadlock_timeout = 1000        # in milliseconds
#max_locks_per_transaction = 64        # min 10
# note: each lock table slot uses ~220 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
#backslash_quote = safe_encoding    # on, off, or safe_encoding
#default_with_oids = off
#escape_string_warning = off
#regex_flavor = advanced        # advanced, extended, or basic
#sql_inheritance = on

# - Other Platforms & Clients -

#transform_null_equals = off


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

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







-----Mensagem original-----
De: Hervé Piedvache [mailto:]
Enviada em: sábado, 28 de julho de 2007 16:57
Para: 
Cc: Bruno Rodrigues Siqueira
Assunto: Re: [PERFORM] select on 1milion register = 6s

Do you have analyzed your table before doing this ?

Le samedi 28 juillet 2007, Bruno Rodrigues Siqueira a écrit :
> Friends,
>
>
>
>
>
>
>
>             Who can help me? My SELECT in a base with 1 milion register,
> using  expression index = 6seconds.
>
>
>
>
>
> Please, I don't  know how to makes it better.
>
>
>
>
>
> Thanks



--
Hervé Piedvache



В списке pgsql-performance по дате сообщения:

От: "Bruno Rodrigues Siqueira"
Дата:
Сообщение: RES: select on 1milion register = 6s
От: "Scott Marlowe"
Дата:
Сообщение: Re: select on 1milion register = 6s