[pgpool-general: 5235] PGPOOL lb issue
ahmad milani
milani.ahmad at gmail.com
Mon Jan 16 19:31:45 JST 2017
Hi,
I have in issue with pgpool2 and cannot figure out why!!!! my setup is as
follows:
singe pgpool to do LB for me
master slave postgress
The issue is as follows, when i send read queries via the pgpool everything
is fine, load get distributed between and master and salve.
but when im doing a query that writes to the database the pgpool again uses
both slave and master and it yeilds error on queries sent to slave.
I have installed 96 on centos.
# ----------------------------
# pgPool-II configuration file
# ----------------------------
#
# This file consists of lines of the form:
#
# name = value
#
# 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
# pgPool-II documentation.
#
# 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 "pgpool reload". Some
# parameters, which are marked below, require a server shutdown and restart
to
# take effect.
#
#-----------------------------------------------------------
-------------------
# CONNECTIONS
#-----------------------------------------------------------
-------------------
# - pgpool Connection Settings -
listen_addresses = '*'
# Host name or IP address to listen on:
# '*' for all, '' for no TCP/IP
connections
# (change requires restart)
port = 5432
# Port number
# (change requires restart)
socket_dir = '/tmp'
# Unix domain socket path
# The Debian package defaults to
# /var/run/postgresql
# (change requires restart)
# - pgpool Communication Manager Connection Settings -
pcp_listen_addresses = '*'
# Host name or IP address for pcp
process to listen on:
# '*' for all, '' for no TCP/IP
connections
# (change requires restart)
pcp_port = 9898
# Port number for pcp
# (change requires restart)
pcp_socket_dir = '/tmp'
# Unix domain socket path for pcp
# The Debian package defaults to
# /var/run/postgresql
# (change requires restart)
listen_backlog_multiplier = 2
# Set the backlog parameter of listen(2)
to
# num_init_children * listen_backlog_multiplier.
# (change requires restart)
serialize_accept = off
# whether to serialize accept() call to
avoid thundering herd problem
# (change requires restart)
# - Backend Connection Settings -
backend_hostname0 = 'pgdb1'
# Host name or IP address to connect to
for backend 0
backend_port0 = 5432
# Port number for backend 0
backend_weight0 = 1
# Weight for backend 0 (only in load
balancing mode)
backend_data_directory0 = '/var/lib/pgsql/9.5/data'
# Data directory for backend 0
backend_flag0 = 'ALLOW_TO_FAILOVER'
# Controls various backend behavior
# ALLOW_TO_FAILOVER or
DISALLOW_TO_FAILOVER
backend_hostname1 = 'pgdb2'
backend_port1 = 5432
backend_weight1 = 1
backend_data_directory1 = '/var/lib/pgsql/9.5/data'
backend_flag1 = 'ALLOW_TO_FAILOVER'
# - Authentication -
enable_pool_hba = on
# Use pool_hba.conf for client
authentication
pool_passwd = 'pool_passwd'
# File name of pool_passwd for md5
authentication.
# "" disables pool_passwd.
# (change requires restart)
authentication_timeout = 60
# Delay in seconds to complete client
authentication
# 0 means no timeout.
# - SSL Connections -
ssl = off
# Enable SSL support
# (change requires restart)
#ssl_key = './server.key'
# Path to the SSL private key file
# (change requires restart)
#ssl_cert = './server.cert'
# Path to the SSL public certificate file
# (change requires restart)
#ssl_ca_cert = ''
# Path to a single PEM format file
# containing CA root certificate(s)
# (change requires restart)
#ssl_ca_cert_dir = ''
# Directory containing CA root
certificate(s)
# (change requires restart)
#-----------------------------------------------------------
-------------------
# POOLS
#-----------------------------------------------------------
-------------------
# - Concurrent session and pool size -
num_init_children = 32
# Number of concurrent sessions allowed
# (change requires restart)
max_pool = 4
# Number of connection pool caches per
connection
# (change requires restart)
# - Life time -
child_life_time = 300
# Pool exits after being idle for this
many seconds
child_max_connections = 0
# Pool exits after receiving that many
connections
# 0 means no exit
connection_life_time = 0
# Connection to backend closes after
being idle for this many seconds
# 0 means no close
client_idle_limit = 0
# Client is disconnected after being
idle for that many seconds
# (even inside an explicit transactions!)
# 0 means no disconnection
#-----------------------------------------------------------
-------------------
# LOGS
#-----------------------------------------------------------
-------------------
# - Where to log -
log_destination = 'stderr'
# Where to log
# Valid values are combinations of
stderr,
# and syslog. Default to stderr.
# - What to log -
log_line_prefix = '%t: pid %p: ' # printf-style string to output at
beginning of each log line.
log_connections = off
# Log connections
log_hostname = off
# Hostname will be shown in ps status
# and in logs if connections are logged
log_statement = off
# Log all statements
log_per_node_statement = off
# Log all statements
# with node and backend informations
log_standby_delay = 'if_over_threshold'
# Log standby delay
# Valid values are combinations of
always,
# if_over_threshold, none
# - Syslog specific -
syslog_facility = 'LOCAL0'
# Syslog local facility. Default to
LOCAL0
syslog_ident = 'pgpool'
# Syslog program identification string
# Default to 'pgpool'
# - Debug -
debug_level = 0
# Debug message verbosity level
# 0 means no message, 1 or more mean
verbose
#log_error_verbosity = default # terse, default, or verbose
messages
#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
#-----------------------------------------------------------
-------------------
# FILE LOCATIONS
#-----------------------------------------------------------
-------------------
pid_file_name = '/var/run/pgpool-II-95/pgpool.pid'
# PID file name
# (change requires restart)
logdir = '/tmp'
# Directory of pgPool status file
# (change requires restart)
#-----------------------------------------------------------
-------------------
# CONNECTION POOLING
#-----------------------------------------------------------
-------------------
connection_cache = on
# Activate connection pools
# (change requires restart)
# Semicolon separated list of queries
# to be issued at the end of a session
# The default is for 8.3 and later
reset_query_list = 'ABORT; DISCARD ALL'
# The following one is for 8.2 and before
#reset_query_list = 'ABORT; RESET ALL; SET SESSION AUTHORIZATION DEFAULT'
#-----------------------------------------------------------
-------------------
# REPLICATION MODE
#-----------------------------------------------------------
-------------------
replication_mode = off
# Activate replication mode
# (change requires restart)
replicate_select = off
# Replicate SELECT statements
# when in replication mode
# replicate_select is higher priority
than
# load_balance_mode.
insert_lock = off
# Automatically locks a dummy row or a
table
# with INSERT statements to keep SERIAL
data
# consistency
# Without SERIAL, no lock will be issued
lobj_lock_table = ''
# When rewriting lo_creat command in
# replication mode, specify table name to
# lock
# - Degenerate handling -
replication_stop_on_mismatch = off
# On disagreement with the packet kind
# sent from backend, degenerate the node
# which is most likely "minority"
# If off, just force to exit this session
failover_if_affected_tuples_mismatch = off
# On disagreement with the number of
affected
# tuples in UPDATE/DELETE queries, then
# degenerate the node which is most
likely
# "minority".
# If off, just abort the transaction to
# keep the consistency
#-----------------------------------------------------------
-------------------
# LOAD BALANCING MODE
#-----------------------------------------------------------
-------------------
load_balance_mode = on
# Activate load balancing mode
# (change requires restart)
ignore_leading_white_space = on
# Ignore leading white spaces of each
query
white_function_list = ''
# Comma separated list of function names
# that don't write to database
# Regexp are accepted
black_function_list = 'currval,lastval,nextval,setval'
# Comma separated list of function names
# that write to database
# Regexp are accepted
database_redirect_preference_list = ''
# comma separated list of pairs of database and node id.
# example: postgres:primary,mydb[0-4]:1,mydb[5-9]:2'
# valid for streaming replicaton mode only.
app_name_redirect_preference_list = ''
# comma separated list of pairs of app name and node id.
# example: 'psql:primary,myapp[0-4]:1,myapp[5-9]:standby'
# valid for streaming replicaton mode only.
allow_sql_comments = off
# if on, ignore SQL comments when judging if load balance or
# query cache is possible.
# If off, SQL comments effectively prevent the judgment
# (pre 3.4 behavior).
#-----------------------------------------------------------
-------------------
# MASTER/SLAVE MODE
#-----------------------------------------------------------
-------------------
master_slave_mode = on
# Activate master/slave mode
# (change requires restart)
master_slave_sub_mode = 'stream'
# Master/slave sub mode
# Valid values are combinations slony or
# stream. Default is slony.
# (change requires restart)
# - Streaming -
sr_check_period = 10
# Streaming replication check period
# Disabled (0) by default
sr_check_user = 'pgpool'
# Streaming replication check user
# This is neccessary even if you disable
streaming
# replication delay check by
sr_check_period = 0
sr_check_password = 'pool'
# Password for streaming replication
check user
sr_check_database = 'postgres'
# Database name for streaming
replication check
delay_threshold = 10000000
# Threshold before not dispatching query
to standby node
# Unit is in bytes
# Disabled (0) by default
# - Special commands -
follow_master_command = ''
# Executes this command after master
failover
# Special values:
# %d = node id
# %h = host name
# %p = port number
# %D = database cluster path
# %m = new master node id
# %H = hostname of the new master node
# %M = old master node id
# %P = old primary node id
# %r = new master port number
# %R = new master database cluster path
# %% = '%' character
#-----------------------------------------------------------
-------------------
# HEALTH CHECK
#-----------------------------------------------------------
-------------------
health_check_period = 10
# Health check period
# Disabled (0) by default
health_check_timeout = 20
# Health check timeout
# 0 means no timeout
health_check_user = 'pgpool'
# Health check user
health_check_password = 'pool'
# Password for health check user
health_check_database = ''
# Database name for health check. If '',
tries 'postgres' frist,
health_check_max_retries = 0
# Maximum number of times to retry a
failed health check before giving up.
health_check_retry_delay = 1
# Amount of time to wait (in seconds)
between retries.
connect_timeout = 10000
# Timeout value in milliseconds before
giving up to connect to backend.
# Default is 10000 ms (10 second). Flaky network user may want to
increase
# the value. 0 means no timeout.
# Note that this value is not only used for health check,
# but also for ordinary conection to backend.
#-----------------------------------------------------------
-------------------
# FAILOVER AND FAILBACK
#-----------------------------------------------------------
-------------------
failover_command = '/etc/pgpool-II-95/failover.sh %d %H'
# Executes this command at failover
# Special values:
# %d = node id
# %h = host name
# %p = port number
# %D = database cluster path
# %m = new master node id
# %H = hostname of the new master node
# %M = old master node id
# %P = old primary node id
# %r = new master port number
# %R = new master database cluster path
# %% = '%' character
failback_command = ''
# Executes this command at failback.
# Special values:
# %d = node id
# %h = host name
# %p = port number
# %D = database cluster path
# %m = new master node id
# %H = hostname of the new master node
# %M = old master node id
# %P = old primary node id
# %r = new master port number
# %R = new master database cluster path
# %% = '%' character
fail_over_on_backend_error = on
# Initiates failover when
reading/writing to the
# backend communication socket fails
# If set to off, pgpool will report an
# error and disconnect the session.
search_primary_node_timeout = 300
# Timeout in seconds to search for the
# primary node when a failover occurs.
# 0 means no timeout, keep searching
# for a primary node forever.
#-----------------------------------------------------------
-------------------
# ONLINE RECOVERY
#-----------------------------------------------------------
-------------------
recovery_user = 'pgpool'
# Online recovery user
recovery_password = 'pool'
# Online recovery password
recovery_1st_stage_command = ''
# Executes a command in first stage
recovery_2nd_stage_command = ''
# Executes a command in second stage
recovery_timeout = 90
# Timeout in seconds to wait for the
# recovering node's postmaster to start
up
# 0 means no wait
client_idle_limit_in_recovery = 0
# Client is disconnected after being idle
# for that many seconds in the second
stage
# of online recovery
# 0 means no disconnection
# -1 means immediate disconnection
#-----------------------------------------------------------
-------------------
# WATCHDOG
#-----------------------------------------------------------
-------------------
# - Enabling -
use_watchdog = off
# Activates watchdog
# (change requires restart)
# -Connection to up stream servers -
trusted_servers = ''
# trusted server list which are used
# to confirm network connection
# (hostA,hostB,hostC,...)
# (change requires restart)
ping_path = '/bin'
# ping command path
# (change requires restart)
# - Watchdog communication Settings -
wd_hostname = ''
# Host name or IP address of this
watchdog
# (change requires restart)
wd_port = 9000
# port number for watchdog service
# (change requires restart)
wd_priority = 1
# priority of this watchdog in leader election
# (change requires restart)
wd_authkey = ''
# Authentication key for watchdog
communication
# (change requires restart)
wd_ipc_socket_dir = '/tmp'
# Unix domain socket path for watchdog IPC socket
# The Debian package defaults to
# /var/run/postgresql
# (change requires restart)
# - Virtual IP control Setting -
delegate_IP = ''
# delegate IP address
# If this is empty, virtual IP never
bring up.
# (change requires restart)
if_cmd_path = '/sbin'
# path to the directory where
if_up/down_cmd exists
# (change requires restart)
if_up_cmd = 'ip addr add $_IP_$/24 dev eth0 label eth0:0'
# startup delegate IP command
# (change requires restart)
if_down_cmd = 'ip addr del $_IP_$/24 dev eth0'
# shutdown delegate IP command
# (change requires restart)
arping_path = '/usr/sbin'
# arping command path
# (change requires restart)
arping_cmd = 'arping -U $_IP_$ -w 1'
# arping command
# (change requires restart)
# - Behaivor on escalation Setting -
clear_memqcache_on_escalation = on
# Clear all the query cache on shared
memory
# when standby pgpool escalate to
active pgpool
# (= virtual IP holder).
# This should be off if client connects
to pgpool
# not using virtual IP.
# (change requires restart)
wd_escalation_command = ''
# Executes this command at escalation
on new active pgpool.
# (change requires restart)
wd_de_escalation_command = ''
# Executes this command when master pgpool resigns from being master.
# (change requires restart)
# - Lifecheck Setting -
# -- common --
wd_monitoring_interfaces_list = '' # Comma separated list of interfaces
names to monitor.
# if any interface from the list is active the watchdog will
# consider the network is fine
# 'any' to enable monitoring on all interfaces except loopback
# '' to disable monitoring
wd_lifecheck_method = 'heartbeat'
# Method of watchdog lifecheck
('heartbeat' or 'query' or 'external')
# (change requires restart)
wd_interval = 10
# lifecheck interval (sec) > 0
# (change requires restart)
# -- heartbeat mode --
wd_heartbeat_port = 9694
# Port number for receiving heartbeat
signal
# (change requires restart)
wd_heartbeat_keepalive = 2
# Interval time of sending heartbeat
signal (sec)
# (change requires restart)
wd_heartbeat_deadtime = 30
# Deadtime interval for heartbeat
signal (sec)
# (change requires restart)
heartbeat_destination0 = 'host0_ip1'
# Host name or IP address of
destination 0
# for sending heartbeat signal.
# (change requires restart)
heartbeat_destination_port0 = 9694
# Port number of destination 0 for
sending
# heartbeat signal. Usually this is the
# same as wd_heartbeat_port.
# (change requires restart)
heartbeat_device0 = ''
# Name of NIC device (such like 'eth0')
# used for sending/receiving heartbeat
# signal to/from destination 0.
# This works only when this is not empty
# and pgpool has root privilege.
# (change requires restart)
#heartbeat_destination1 = 'host0_ip2'
#heartbeat_destination_port1 = 9694
#heartbeat_device1 = ''
# -- query mode --
wd_life_point = 3
# lifecheck retry times
# (change requires restart)
wd_lifecheck_query = 'SELECT 1'
# lifecheck query to pgpool from
watchdog
# (change requires restart)
wd_lifecheck_dbname = 'template1'
# Database name connected for lifecheck
# (change requires restart)
wd_lifecheck_user = 'nobody'
# watchdog user monitoring pgpools in
lifecheck
# (change requires restart)
wd_lifecheck_password = ''
# Password for watchdog user in
lifecheck
# (change requires restart)
# - Other pgpool Connection Settings -
#other_pgpool_hostname0 = 'host0'
# Host name or IP address to connect to
for other pgpool 0
# (change requires restart)
#other_pgpool_port0 = 5432
# Port number for othet pgpool 0
# (change requires restart)
#other_wd_port0 = 9000
# Port number for othet watchdog 0
# (change requires restart)
#other_pgpool_hostname1 = 'host1'
#other_pgpool_port1 = 5432
#other_wd_port1 = 9000
#-----------------------------------------------------------
-------------------
# OTHERS
#-----------------------------------------------------------
-------------------
relcache_expire = 0
# Life time of relation cache in seconds.
# 0 means no cache expiration(the
default).
# The relation cache is used for cache
the
# query result against PostgreSQL system
# catalog to obtain various information
# including table structures or if it's a
# temporary table or not. The cache is
# maintained in a pgpool child local
memory
# and being kept as long as it survives.
# If someone modify the table by using
# ALTER TABLE or some such, the relcache
is
# not consistent anymore.
# For this purpose, cache_expiration
# controls the life time of the cache.
relcache_size = 256
# Number of relation cache
# entry. If you see frequently:
# "pool_search_relcache: cache replacement happend"
# in the pgpool log, you might want to increate this number.
check_temp_table = on
# If on, enable temporary table check in
SELECT statements.
# This initiates queries against system
catalog of primary/master
# thus increases load of master.
# If you are absolutely sure that your system never uses temporary tables
# and you want to save access to primary/master, you could turn this off.
# Default is on.
check_unlogged_table = on
# If on, enable unlogged table check in
SELECT statements.
# This initiates queries against system
catalog of primary/master
# thus increases load of master.
# If you are absolutely sure that your
system never uses unlogged tables
# and you want to save access to
primary/master, you could turn this off.
# Default is on.
#-----------------------------------------------------------
-------------------
# IN MEMORY QUERY MEMORY CACHE
#-----------------------------------------------------------
-------------------
memory_cache_enabled = off
# If on, use the memory cache functionality, off by default
memqcache_method = 'shmem'
# Cache storage method. either 'shmem'(shared memory) or
# 'memcached'. 'shmem' by default
# (change requires restart)
memqcache_memcached_host = 'localhost'
# Memcached host name or IP address. Mandatory if
# memqcache_method = 'memcached'.
# Defaults to localhost.
# (change requires restart)
memqcache_memcached_port = 11211
# Memcached port number. Mondatory if memqcache_method = 'memcached'.
# Defaults to 11211.
# (change requires restart)
memqcache_total_size = 67108864
# Total memory size in bytes for storing memory cache.
# Mandatory if memqcache_method = 'shmem'.
# Defaults to 64MB.
# (change requires restart)
memqcache_max_num_cache = 1000000
# Total number of cache entries. Mandatory
# if memqcache_method = 'shmem'.
# Each cache entry consumes 48 bytes on shared memory.
# Defaults to 1,000,000(45.8MB).
# (change requires restart)
memqcache_expire = 0
# Memory cache entry life time specified in seconds.
# 0 means infinite life time. 0 by default.
# (change requires restart)
memqcache_auto_cache_invalidation = on
# If on, invalidation of query cache is triggered by corresponding
# DDL/DML/DCL(and memqcache_expire). If off, it is only triggered
# by memqcache_expire. on by default.
# (change requires restart)
memqcache_maxcache = 409600
# Maximum SELECT result size in bytes.
# Must be smaller than memqcache_cache_block_size. Defaults to 400KB.
# (change requires restart)
memqcache_cache_block_size = 1048576
# Cache block size in bytes. Mandatory if memqcache_method = 'shmem'.
# Defaults to 1MB.
# (change requires restart)
memqcache_oiddir = '/var/log/pgpool/oiddir'
# Temporary work directory to record table oids
# (change requires restart)
white_memqcache_table_list = ''
# Comma separated list of table names to
memcache
# that don't write to database
# Regexp are accepted
black_memqcache_table_list = ''
# Comma separated list of table names
not to memcache
# that don't write to database
# Regexp are accepted
---------+----------+------+--------+-----------+---------+------------
0 | pgdb1 | 5432 | 2 | 0.500000 | primary | 10581
1 | pgdb2 | 5432 | 2 | 0.500000 | standby | 2351
Role | Name | Upstream | Connection String
----------+-------|----------|-------------------------------------
standby | pgdb2 | | host=pgdb2 user=repmgr dbname=repmgr
* master | pgdb1 | | host=pgdb1 user=repmgr dbname=repmgr
The errors I see on the web server:
PreventCommandIfReadOnly
cannot execute SELECT in a read-only transaction
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.sraoss.jp/pipermail/pgpool-general/attachments/20170116/7bfd2452/attachment-0001.html>
More information about the pgpool-general
mailing list