Re: System Load analyze - Mailing list pgsql-general
| From | Pavel Stehule |
|---|---|
| Subject | Re: System Load analyze |
| Date | |
| Msg-id | 162867790711250247tc32f521wfdf1163004c74e44@mail.gmail.com Whole thread Raw |
| In response to | System Load analyze (Peter Bauer <peter.bauer@apus.co.at>) |
| List | pgsql-general |
Hello maybe you have to tune bgwriter. Please, read this article http://www.westnet.com/~gsmith/content/postgresql/chkp-bgw-83.htm Regards Pavel Stehule On 25/11/2007, Peter Bauer <peter.bauer@apus.co.at> wrote: > > Hi all, > > i have a system here with 2 2.4GHz Xeon Processors, 2GB RAM, ONE Disk on > a Battery Backed Write Cache SCSI Controller and PostgreSQL 8.1.4 > running with the data on a DRBD Device for High Availability. The used > database is also replicated to two similar machines with slony1. > > Since the load average is between 1 (most of the time) and 10 (peeks) i > am worried about the load and executed vmstat and iostat which show that > 1000-6000 Blocks are writen per second. Please check the attached output > for further details. > top shows that the CPUs are at least 80% idle most of the time so i > think there is an I/O bottleneck. I'm aware that this hardware setup is > probably not sufficient but is would like to investigate how critical > the situation is. > > thanks, > Peter > > > > procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu---- > r b swpd free buff cache si so bi bo in cs us sy id wa > 0 0 398256 78328 140612 1063556 0 0 0 1472 2029 5081 4 3 92 0 > 0 2 398256 78268 140612 1063576 0 0 0 2304 1928 4216 0 2 98 0 > 1 2 398256 78100 140612 1063576 0 0 0 1464 1716 3994 1 3 96 0 > 0 0 398256 78704 140612 1063592 0 0 0 916 1435 3570 5 3 91 0 > 0 0 398256 77876 140612 1063616 0 0 0 0 305 1169 3 1 96 0 > 0 1 398256 79200 140612 1063628 0 0 0 2404 2787 6555 7 6 86 0 > 0 2 398256 79256 140612 1063660 0 0 0 1564 1640 3577 4 2 94 0 > 0 0 398256 79324 140612 1063692 0 0 0 1660 2322 5615 5 2 93 0 > 0 0 398256 78668 140612 1063724 0 0 0 1048 1390 4197 16 13 72 0 > 1 0 398256 79344 140612 1063748 0 0 0 1896 2416 5675 5 5 89 0 > 0 0 398256 79336 140612 1063784 0 0 0 1176 1720 4436 5 3 92 0 > 1 2 398256 79280 140612 1063812 0 0 0 1800 1697 3931 3 3 94 0 > 0 1 398256 79048 140612 1063832 0 0 0 1384 1733 4137 4 2 93 0 > 0 1 398256 78792 140612 1063868 0 0 0 1672 2163 5241 3 2 94 0 > 0 0 398256 77608 140612 1063880 0 0 0 1088 1638 3484 4 2 93 0 > 0 0 398256 79108 140612 1063884 0 0 0 1568 2103 5382 7 5 88 0 > 0 0 398256 79100 140612 1063892 0 0 0 1556 1394 3135 2 1 97 0 > 0 2 398256 79084 140612 1063900 0 0 0 1644 2072 4953 2 0 97 0 > 0 0 398256 79060 140612 1063932 0 0 0 1240 1714 3888 5 2 92 0 > 0 2 398256 79032 140612 1063940 0 0 0 1328 1694 4135 4 2 94 0 > 0 1 398256 78452 140612 1063944 0 0 0 620 925 2824 6 7 87 0 > 0 0 398256 79036 140612 1063956 0 0 0 1196 1293 2954 6 7 87 0 > 0 2 398256 79136 140612 1063964 0 0 0 1736 1959 4494 4 2 94 0 > 0 0 398256 79132 140612 1063964 0 0 0 4 260 1039 1 1 98 0 > 0 0 398256 79052 140612 1063980 0 0 0 2444 3084 6955 6 5 89 0 > 0 2 398256 79060 140612 1063988 0 0 0 948 1146 3616 3 1 96 0 > 0 1 398256 78268 140612 1064056 0 0 0 1908 1809 4086 6 5 88 0 > 0 1 398256 76728 140612 1064056 0 0 0 6256 6637 15472 5 5 90 0 > 0 2 398256 77000 140612 1064064 0 0 0 4916 5840 12107 1 4 95 0 > 0 2 398256 76956 140612 1064068 0 0 0 6468 7432 15211 1 3 96 0 > 0 6 398256 77388 140612 1064072 0 0 0 8116 7826 18265 1 8 91 0 > 0 2 398256 74312 140612 1064076 0 0 0 7032 6886 16136 2 7 91 0 > 0 2 398256 74264 140612 1064076 0 0 0 5680 7143 13411 0 5 95 0 > 0 2 398256 72980 140612 1064140 0 0 0 5396 6377 13251 6 6 88 0 > 0 3 398256 76972 140612 1064148 0 0 0 5652 6793 14079 4 9 87 0 > 0 2 398256 77836 140612 1064148 0 0 0 3968 5321 14187 10 8 82 0 > 1 0 398256 77280 140612 1064148 0 0 0 1608 3188 8974 21 12 67 0 > 1 0 398256 77832 140612 1064152 0 0 0 236 834 2625 7 5 87 0 > 0 0 398256 77464 140612 1064152 0 0 0 244 505 1378 2 4 94 0 > 1 0 398256 77828 140612 1064164 0 0 0 316 580 1954 7 2 91 0 > 0 0 398256 77804 140612 1064180 0 0 0 740 673 2248 2 2 96 0 > 0 0 398256 77000 140612 1064180 0 0 0 304 589 1739 1 3 96 0 > 0 0 398256 77000 140612 1064184 0 0 0 0 216 886 0 1 99 0 > 0 0 398256 75452 140612 1064184 0 0 0 432 755 2032 6 1 93 0 > 0 0 398256 76964 140616 1064200 0 0 0 1980 2722 6452 7 2 91 0 > 0 0 398256 77040 140616 1064212 0 0 0 1524 1536 3635 5 1 93 0 > 0 2 398256 77028 140616 1064216 0 0 0 1136 1489 3342 1 2 97 0 > 0 0 398256 76976 140616 1064236 0 0 0 1392 1831 4468 3 2 94 0 > 0 0 398256 76944 140616 1064256 0 0 0 932 1374 3318 7 8 85 0 > 0 0 398256 76856 140616 1064276 0 0 0 1392 1773 3985 5 4 91 0 > 1 4 398256 76536 140616 1064448 0 0 0 1432 1537 3950 4 2 94 0 > 0 0 398256 76640 140616 1064308 0 0 0 560 865 2577 6 3 91 0 > 0 0 398256 76368 140616 1064328 0 0 0 1752 1973 4424 3 3 94 0 > 0 0 398256 74732 140616 1064340 0 0 0 1244 1807 3758 4 6 90 0 > 1 2 398256 76244 140616 1064352 0 0 0 876 1189 3579 4 2 94 0 > 0 0 398256 76192 140616 1064360 0 0 0 1856 1623 3727 5 4 91 0 > 0 0 398256 76236 140616 1064372 0 0 0 1292 1748 3664 5 4 91 0 > 0 0 398256 76548 140616 1064392 0 0 0 0 338 1810 11 5 84 0 > 0 0 398256 76540 140616 1064392 0 0 0 0 278 1055 2 4 93 0 > > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 241.00 0.00 6344.00 0 6344 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 39.00 0.00 1240.00 0 1240 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 170.00 0.00 3944.00 0 3944 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 173.00 0.00 3880.00 0 3880 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 73.00 0.00 2656.00 0 2656 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 120.00 0.00 2656.00 0 2656 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 81.00 0.00 2184.00 0 2184 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 133.00 0.00 3144.00 0 3144 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 115.00 0.00 2936.00 0 2936 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 64.00 0.00 2080.00 0 2080 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 176.00 0.00 4384.00 0 4384 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 172.00 0.00 3296.00 0 3296 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 191.00 0.00 3880.00 0 3880 > dev8-1 0.00 0.00 0.00 0 0 > > Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn > dev8-0 144.00 0.00 2464.00 0 2464 > dev8-1 0.00 0.00 0.00 0 0 > > > > #--------------------------------------------------------------------------- > # 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 = '/clstsql/data' # btaf: Data Directory on the drbd device, APUS > > #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 > #--------------------------------------------------------------------------- > > # - Connection Settings - > > listen_addresses = '*' # btaf: '*' = Listen to all addresses > port = 5432 # btaf: Use default port for PostgreSQL, APUS > > max_connections = 400 # btaf: APUS > # 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 = 2 > unix_socket_directory = '/var/run/postgresql' > #unix_socket_group = '' > #unix_socket_permissions = 0777 # octal > #bonjour_name = '' # defaults to the computer name > > # - Security & Authentication - > > #authentication_timeout = 60 # 1-600, in seconds > > ssl = false # btaf: Do not use ssl for connections, APUS > > #password_encryption = on > #db_user_namespace = off > > # Kerberos > #krb_server_keyfile = '' > #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; > # 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 = 40000 # min 16 or max_connections*2, 8KB each, APUS > temp_buffers = 8000 # min 100, 8KB each, APUS > #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). > work_mem = 20480 # min 64, size in KB, APUS > maintenance_work_mem = 51200 # min 1024, size in KB, APUS > #max_stack_depth = 2048 # min 100, size in KB > > # - Free Space Map - > > max_fsm_pages = 40000 # min max_fsm_relations*16, 6 bytes each, APUS > #max_fsm_relations = 1000 # min 100, ~70 bytes each > > # - Kernel Resource Usage - > > #max_files_per_process = 1000 # min 25 > #preload_libraries = '' > > # - 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 > > # - Background writer - > > bgwriter_delay = 100 # 10-10000 milliseconds between rounds, APUS > bgwriter_lru_percent = 2.0 # 0-100% of LRU buffers scanned/round, APUS > bgwriter_lru_maxpages = 10 # 0-1000 buffers max written/round, APUS > bgwriter_all_percent = 1 # 0-100% of all buffers scanned/round, APUS > bgwriter_all_maxpages = 10 # 0-1000 buffers max written/round, APUS > > > #--------------------------------------------------------------------------- > # 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 = 8 # min 4, 8KB each > #commit_delay = 0 # range 0-100000, in microseconds > #commit_siblings = 5 # range 1-1000 > > # - Checkpoints - > > checkpoint_segments = 32 # in logfile segments, min 1, 16MB each, APUS > #checkpoint_timeout = 300 # range 30-3600, in seconds > checkpoint_warning = 100 # in seconds, 0 is off, APUS > > # - Archiving - > > #archive_command = '' # command to use to archive a logfile > # segment > > > #--------------------------------------------------------------------------- > # 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 - > > effective_cache_size = 89600 # typically 8KB each, APUS > #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) > > # - 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 > > > #--------------------------------------------------------------------------- > # 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 > > # 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 # If on, any 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 = 1440 # Automatic rotation of logfiles will > # happen after so many minutes. 0 to > # disable. > #log_rotation_size = 10240 # Automatic rotation of logfiles will > # happen after so many kilobytes of 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 = panic # Values in order of increasing severity: > # debug5 > # debug4 > # debug3 > # debug2 > # debug1 > # info > # notice > # warning > # error > # panic(off) > > log_min_duration_statement = 1000 # -1 is disabled, 0 logs all statements > # and their durations, in milliseconds. > > #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 = '[%d %m]' # 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, 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 = on > stats_command_string = on > #stats_block_level = off > stats_row_level = on > #stats_reset_on_server_start = off > > > #--------------------------------------------------------------------------- > # AUTOVACUUM PARAMETERS > #--------------------------------------------------------------------------- > > autovacuum = on # enable autovacuum subprocess? > autovacuum_naptime = 30 # time between autovacuum runs, in secs, APUS > autovacuum_vacuum_threshold = 500 # min # of tuple updates before, APUS > # vacuum > autovacuum_analyze_threshold = 250 # min # of tuple updates before, APUS > # analyze > autovacuum_vacuum_scale_factor = 0.2 # fraction of rel size before, APUS > # vacuum > autovacuum_analyze_scale_factor = 0.1 # fraction of rel size before, APUS > # analyze > #autovacuum_vacuum_cost_delay = -1 # default vacuum cost delay for > # autovac, -1 means use > # vacuum_cost_delay > #autovacuum_vacuum_cost_limit = -1 # default vacuum cost limit for > # autovac, -1 means use > # vacuum_cost_limit > > > #--------------------------------------------------------------------------- > # CLIENT CONNECTION DEFAULTS > #--------------------------------------------------------------------------- > > # - Statement Behavior - > > #search_path = '$user,public' # schema names > #default_tablespace = '' # a tablespace name, '' uses > # the default > #check_function_bodies = on > #default_transaction_isolation = 'read committed' > #default_transaction_read_only = off > statement_timeout = 60000 # 0 is disabled, in milliseconds, APUS > > # - Locale and Formatting - > > #datestyle = 'iso, mdy' > #timezone = unknown # actually, defaults to TZ > # environment setting > #australian_timezones = off > #extra_float_digits = 0 # min -15, max 2 > #client_encoding = sql_ascii # actually, defaults to database > # encoding > > # These settings are initialized by initdb -- they might be changed > lc_messages = 'C' # locale for system error message > # strings > lc_monetary = 'C' # locale for monetary formatting > lc_numeric = 'C' # locale for number formatting > lc_time = 'C' # locale for time formatting > > # - Other Defaults - > > #explain_pretty_print = on > #dynamic_library_path = '$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 = on # btaf: Add missing FROM clauses to improve compatibility with 7.4.x versions > > #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 > > > > ---------------------------(end of broadcast)--------------------------- > TIP 9: In versions below 8.0, the planner will ignore your desire to > choose an index scan if your joining column's datatypes do not > match > >
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