[转帖]PostgreSQL 参数优化设置 32GB内存（推荐） 内存参数 检查点 日志参数 自动初始化参数shell脚本

1.修改参数列表

（1）执行计划

enable_nestloop = off #默认为on

enable_seqscan = off #默认为on

enable_indexscan = on

enable_bitmapscan = on

max_connections = 1000 #默认为100

 

（2）内存相关

shared_buffers = 16GB # 默认为128MB

effective_cache_size = 24GB #默认为4GB

work_mem = 32MB

temp_buffers = 32MB

wal_buffers = 512MB

maintenance_work_mem = 2GB

 

（3）autovacuum

autovacuum = on

autovacuum_max_workers = 3 #默认为3

autovacuum_work_mem = 256MB

autovacuum_vacuum_scale_factor = 0.05 #默认为0.2

 

（4）检查点

max_wal_size = 4GB #默认为1GB

min_wal_size = 1GB #默认为80MB

checkpoint_completion_target = 0.9 #默认为0.5

checkpoint_timeout = 30min #默认为5min

 

（5）日志

log_destination = csvlog

log_directory = pg_log

logging_collector = on

log_min_duration_statement = 800

log_rotation_size = 1024MB

log_truncate_on_rotation = on

log_filename = 'xl_log_%a.log'

 

2.参数设置公式

这个shell脚本可以使用shell的关联数组对

#!/bin/bash





#command to execute script: su - postgres -c "./create.sh"





#default value refer to standard server(cpu:6cores,memory:32G,storage:12T)





#value according to the actual situation 





 





#List of parameters to be modified





:<<!





	enable_seqscan = off





	enable_indexscan = on





	enable_bitmapscan = on





	max_connections = 1000





	shared_buffers = 16GB





	effective_cache_size = 24GB





	work_mem = 32MB





	temp_buffers = 32MB





	wal_buffers = 512MB





	maintenance_work_mem = 2GB





	autovacuum_max_workers = 3





	autovacuum_work_mem = 256MB





	checkpoint_timeout = 30min





	max_wal_size = 4GB





	min_wal_size = 1GB





	checkpoint_completion_target = 0.9





	log_destination = csvlog





	log_directory = pg_log





	logging_collector = on





	log_min_duration_statement = 800





	log_rotation_size = 1024MB





	log_truncate_on_rotation = on





	log_filename = 'xl_log_%a.log'





!





 





ERROR="\033[41;37m ERROR \033[0m"





INFO="\033[42;37m INFO \033[0m"





WARN="\033[43;37m WARN \033[0m"





COMMON_ERROR="some error happened, specific information please see console output"





 





# Array of parameters





declare -A parameter_array





parameter_array=([enable_seqscan]=off [enable_indexscan]=on [enable_bitmapscan]=on [max_connections]=1000 [shared_buffers]=16GB 





[effective_cache_size]=24GB [work_mem]=32MB [temp_buffers]=32MB [wal_buffers]=512MB [maintenance_work_mem]=2GB 





[autovacuum_max_workers]=3 [autovacuum_work_mem]=256MB [checkpoint_timeout]=30min [max_wal_size]=4GB 





[min_wal_size]=1GB [checkpoint_completion_target]=0.9 [log_destination]=csvlog [log_directory]=pg_log 





[logging_collector]=on [log_min_duration_statement]=800 [log_rotation_size]=1024MB [log_truncate_on_rotation]=on [log_filename]=viid_log_%a.log )





 





#default value :





pgctl_path=





data_directory=





memory=





 





# check command exit value, 0 is success





function check_fun(){





	status=$?





	error=${COMMON_ERROR}





	if [[ 0 -ne ${status} ]] ; then





		echo -e "${ERROR} ${error}"





		exit 1





	fi





}





 





# prepare conditions





function prepare_conditions(){





	data_directory=$(psql -qtAX  -c "show data_directory" | sed 's/[ ]//g')





	check_fun





	if [[ ! -d "${data_directory}" ]] ; then





		echo -e "${ERROR} database's data directory does not exist"





		exit 1





	fi





	# physical machine environment





	memory=$(grep MemTotal /proc/meminfo | awk '{print $2 / 1024 / 1024}' | sed 's/\.[0-9]*//' | tail -n 1)





	check_fun





	# docker environment 





	memory_limit=$(($(awk '{print $1}' /sys/fs/cgroup/memory/memory.limit_in_bytes) / 1024 / 1024 /1024))





	check_fun





	# comparing the two, choose the smaller one.





	if [[ "${memory_limit}" -le "${memory}" ]] ; then





		memory=${memory_limit}





	fi





}





 





# calculate parameters





function calculate_parameters(){





	# 50%*memory





	parameter_array[shared_buffers]=$((memory * 1024 / 2))"MB"





	# 75%*memory





	parameter_array[effective_cache_size]=$((memory * 1024 * 3 / 4 ))"MB"





	# <1%





	parameter_array[work_mem]=${memory}"MB"





	# <1%





	parameter_array[temp_buffers]=${memory}"MB"





	# 32GB => 512MB





	parameter_array[wal_buffers]=$((memory * 16 ))"MB"





	# 32GB => 2048MB





	parameter_array[maintenance_work_mem]=$((memory * 64 ))"MB"





}





 





# modify parameters





function modify_parameters(){





	# modify parameters by modifying file postgresql.conf:





	for parameter in ${!parameter_array[*]}





	do





		#check whether the parameters have been modified





		# PostgreSQL's default parameter configuration example: enable_seqscan = on





		# viid's example: enable_seqscan='on'





		check_out=$(grep "^${parameter}=" "${data_directory}"/postgresql.conf | grep -v '#' | tail -n 1)





		# process sleep 





		sleep 0.2s





		if [[ -z "${check_out}" ]] ; then





			echo "${parameter}='${parameter_array[${parameter}]}'" >> "${data_directory}"/postgresql.conf





			check_fun





			echo -e "${INFO} modify ${parameter} successfully"





		else 





			if [[ "${check_out}" = "${parameter}='${parameter_array[${parameter}]}'" ]] ; then





				echo -e "${INFO} ${parameter} is already configured, then skip this step"





			else





				sed -i s!^"${check_out}"!"${parameter}='${parameter_array[${parameter}]}'"!g  "${data_directory}"/postgresql.conf





				check_fun





				echo -e "${INFO} modify ${parameter} successfully"





			fi





		fi





	done





}





 





# create directory(pg_log and pg_arch), and set user postgres permission





function create_dir(){





	directory_array=("pg_arch" "pg_log")





	for directory in ${directory_array[*]};





	do





		# process sleep 





		sleep 0.2s





		if [[ ! -d "${data_directory}/${directory}" ]] ; then





			mkdir -p "${data_directory}"/"${directory}"





			echo -e "${INFO} path ${data_directory}/${directory} create successfully"





		else 





			echo -e "${INFO} ${data_directory}/${directory} is already exists, then skip this step"





		fi





	# set user postgres permission





	chown postgres:postgres "${data_directory}"/"${directory}"





	done





}





 





# because the environment is different, need to find the path of the database restart command 'pg_ctl'





function find_cmd(){





	result=$(find / -name pg_ctl 2> /dev/null | grep bin/pg_ctl$ | tail -n 1 )





	# check whether the path exists





	if [[ -z "${result}" ]] ; then





		echo -e "${ERROR} database restart command 'pg_ctl' not exists"





		echo -e "${ERROR} please check to see if the database is installed or the command directory does not have permission to access it"





		exit 1





	else 





		echo -e "${INFO} database restart command 'pg_ctl' path: ${result}"





		pgctl_path=${result}





	fi





}





 





# user choose whether to restart or not





function check_restart(){





	read -r -p "Is it necessary to restart database immediately?[Enter YES or NO]:" result





	if [[ "${result,,}" = "yes" ]] ; then





		echo -e "${INFO} start to restart database"





		${pgctl_path} restart -D "${data_directory}" >& /dev/null





		if [[ 0 -ne ${status} ]] ; then





			echo -e "${ERROR} restart database failed"





			exit 12





		fi





	elif [[ "${result,,}" = "no" ]] ; then





		echo -e "${WARN} please restart database manually"





		echo -e "${WARN} if you don't restart, database may not be available"





		exit 11





	else





		echo -e "${ERROR} invalid input,please enter again"





		check_restart





	fi





}





 





# ******* start *******





# prepare conditions:memory ,data_directory





prepare_conditions





# calculate parameters





calculate_parameters





# modify parameters





modify_parameters 





# create directory(pg_log and pg_arch)





create_dir





# the path of the database restart command 'pg_ctl'





find_cmd





# remind user that they need to restart database to take effect





# process sleep 





sleep 0.5s





echo -e ""





echo -e "*******************************************************************"





echo -e "*                                                                 *"





echo -e "*                                                                 *"





echo -e "*                restart database to take effect                  *"





echo -e "*                                                                 *"





echo -e "*                                                                 *"





echo -e "*******************************************************************"





# process sleep 





sleep 0.5s





# user choose whether to restart or not 





# check_restart





echo -e "${INFO} start to restart database"





${pgctl_path} restart -D "${data_directory}" >& /dev/null





 

文章知识点与官方知识档案匹配，可进一步学习相关知识

PostgreSQL技能树首页概览6104 人正在系统学习中