【监控】Linux部署postgres_exporter及PG配置（非Docker）

一、下载及部署

下载地址

选一个amd64下载

上传至服务器，解压

tax -xvf postgres_exporter-0.11.1.linux-amd64.tar.gz

进入解压后的目录

二、postgres_exporter配置

1. 停止脚本stop.sh

建立停止脚本 stop.sh 。注意unix编码

#!/bin/sh
echo "stop"
#!/bin/bashPID=$(ps -ef | grep postgres_exporter | grep -v grep | awk '{ print $2 }')
if [ "${PID}" ]
thenecho 'Application is stpping...'echo kill $PID DONEkill $PID
elseecho 'Application is already stopped...'
fi

2. 启动脚本start.sh

启动脚本start.sh

• 后面会建立postgres_exporter用户，密码为password

• –web.listen-address为监听的端口

• –extend.query-path为自定义查询的文件

sh stop.sh
export DATA_SOURCE_NAME=postgresql://postgres_exporter:password@数据库IP:数据库端口/postgres?sslmode=disablenohup ./postgres_exporter --web.listen-address=0.0.0.0:8001 --extend.query-path=queries.yaml >nohup.out 2>&1 &

3. queries.yaml

pg_replication:query: "SELECT CASE WHEN NOT pg_is_in_recovery() THEN 0 ELSE GREATEST (0, EXTRACT(EPOCH FROM (now() - pg_last_xact_replay_timestamp()))) END AS lag"master: truemetrics:- lag:usage: "GAUGE"description: "Replication lag behind master in seconds"pg_postmaster:query: "SELECT pg_postmaster_start_time as start_time_seconds from pg_postmaster_start_time()"master: truemetrics:- start_time_seconds:usage: "GAUGE"description: "Time at which postmaster started"pg_stat_user_tables:query: |SELECTcurrent_database() datname,schemaname,relname,seq_scan,seq_tup_read,idx_scan,idx_tup_fetch,n_tup_ins,n_tup_upd,n_tup_del,n_tup_hot_upd,n_live_tup,n_dead_tup,n_mod_since_analyze,COALESCE(last_vacuum, '1970-01-01Z') as last_vacuum,COALESCE(last_autovacuum, '1970-01-01Z') as last_autovacuum,COALESCE(last_analyze, '1970-01-01Z') as last_analyze,COALESCE(last_autoanalyze, '1970-01-01Z') as last_autoanalyze,vacuum_count,autovacuum_count,analyze_count,autoanalyze_countFROMpg_stat_user_tablesmetrics:- datname:usage: "LABEL"description: "Name of current database"- schemaname:usage: "LABEL"description: "Name of the schema that this table is in"- relname:usage: "LABEL"description: "Name of this table"- seq_scan:usage: "COUNTER"description: "Number of sequential scans initiated on this table"- seq_tup_read:usage: "COUNTER"description: "Number of live rows fetched by sequential scans"- idx_scan:usage: "COUNTER"description: "Number of index scans initiated on this table"- idx_tup_fetch:usage: "COUNTER"description: "Number of live rows fetched by index scans"- n_tup_ins:usage: "COUNTER"description: "Number of rows inserted"- n_tup_upd:usage: "COUNTER"description: "Number of rows updated"- n_tup_del:usage: "COUNTER"description: "Number of rows deleted"- n_tup_hot_upd:usage: "COUNTER"description: "Number of rows HOT updated (i.e., with no separate index update required)"- n_live_tup:usage: "GAUGE"description: "Estimated number of live rows"- n_dead_tup:usage: "GAUGE"description: "Estimated number of dead rows"- n_mod_since_analyze:usage: "GAUGE"description: "Estimated number of rows changed since last analyze"- last_vacuum:usage: "GAUGE"description: "Last time at which this table was manually vacuumed (not counting VACUUM FULL)"- last_autovacuum:usage: "GAUGE"description: "Last time at which this table was vacuumed by the autovacuum daemon"- last_analyze:usage: "GAUGE"description: "Last time at which this table was manually analyzed"- last_autoanalyze:usage: "GAUGE"description: "Last time at which this table was analyzed by the autovacuum daemon"- vacuum_count:usage: "COUNTER"description: "Number of times this table has been manually vacuumed (not counting VACUUM FULL)"- autovacuum_count:usage: "COUNTER"description: "Number of times this table has been vacuumed by the autovacuum daemon"- analyze_count:usage: "COUNTER"description: "Number of times this table has been manually analyzed"- autoanalyze_count:usage: "COUNTER"description: "Number of times this table has been analyzed by the autovacuum daemon"pg_statio_user_tables:query: "SELECT current_database() datname, schemaname, relname, heap_blks_read, heap_blks_hit, idx_blks_read, idx_blks_hit, toast_blks_read, toast_blks_hit, tidx_blks_read, tidx_blks_hit FROM pg_statio_user_tables"metrics:- datname:usage: "LABEL"description: "Name of current database"- schemaname:usage: "LABEL"description: "Name of the schema that this table is in"- relname:usage: "LABEL"description: "Name of this table"- heap_blks_read:usage: "COUNTER"description: "Number of disk blocks read from this table"- heap_blks_hit:usage: "COUNTER"description: "Number of buffer hits in this table"- idx_blks_read:usage: "COUNTER"description: "Number of disk blocks read from all indexes on this table"- idx_blks_hit:usage: "COUNTER"description: "Number of buffer hits in all indexes on this table"- toast_blks_read:usage: "COUNTER"description: "Number of disk blocks read from this table's TOAST table (if any)"- toast_blks_hit:usage: "COUNTER"description: "Number of buffer hits in this table's TOAST table (if any)"- tidx_blks_read:usage: "COUNTER"description: "Number of disk blocks read from this table's TOAST table indexes (if any)"- tidx_blks_hit:usage: "COUNTER"description: "Number of buffer hits in this table's TOAST table indexes (if any)"# WARNING: This set of metrics can be very expensive on a busy server as every unique query executed will create an additional time series
pg_stat_statements:query: "SELECT t2.rolname, t3.datname, queryid, calls, total_time / 1000 as total_time_seconds, min_time / 1000 as min_time_seconds, max_time / 1000 as max_time_seconds, mean_time / 1000 as mean_time_seconds, stddev_time / 1000 as stddev_time_seconds, rows, shared_blks_hit, shared_blks_read, shared_blks_dirtied, shared_blks_written, local_blks_hit, local_blks_read, local_blks_dirtied, local_blks_written, temp_blks_read, temp_blks_written, blk_read_time / 1000 as blk_read_time_seconds, blk_write_time / 1000 as blk_write_time_seconds FROM pg_stat_statements t1 JOIN pg_roles t2 ON (t1.userid=t2.oid) JOIN pg_database t3 ON (t1.dbid=t3.oid) WHERE t2.rolname != 'rdsadmin'"master: truemetrics:- rolname:usage: "LABEL"description: "Name of user"- datname:usage: "LABEL"description: "Name of database"- queryid:usage: "LABEL"description: "Query ID"- calls:usage: "COUNTER"description: "Number of times executed"- total_time_seconds:usage: "COUNTER"description: "Total time spent in the statement, in milliseconds"- min_time_seconds:usage: "GAUGE"description: "Minimum time spent in the statement, in milliseconds"- max_time_seconds:usage: "GAUGE"description: "Maximum time spent in the statement, in milliseconds"- mean_time_seconds:usage: "GAUGE"description: "Mean time spent in the statement, in milliseconds"- stddev_time_seconds:usage: "GAUGE"description: "Population standard deviation of time spent in the statement, in milliseconds"- rows:usage: "COUNTER"description: "Total number of rows retrieved or affected by the statement"- shared_blks_hit:usage: "COUNTER"description: "Total number of shared block cache hits by the statement"- shared_blks_read:usage: "COUNTER"description: "Total number of shared blocks read by the statement"- shared_blks_dirtied:usage: "COUNTER"description: "Total number of shared blocks dirtied by the statement"- shared_blks_written:usage: "COUNTER"description: "Total number of shared blocks written by the statement"- local_blks_hit:usage: "COUNTER"description: "Total number of local block cache hits by the statement"- local_blks_read:usage: "COUNTER"description: "Total number of local blocks read by the statement"- local_blks_dirtied:usage: "COUNTER"description: "Total number of local blocks dirtied by the statement"- local_blks_written:usage: "COUNTER"description: "Total number of local blocks written by the statement"- temp_blks_read:usage: "COUNTER"description: "Total number of temp blocks read by the statement"- temp_blks_written:usage: "COUNTER"description: "Total number of temp blocks written by the statement"- blk_read_time_seconds:usage: "COUNTER"description: "Total time the statement spent reading blocks, in milliseconds (if track_io_timing is enabled, otherwise zero)"- blk_write_time_seconds:usage: "COUNTER"description: "Total time the statement spent writing blocks, in milliseconds (if track_io_timing is enabled, otherwise zero)"pg_process_idle:query: |WITHmetrics AS (SELECTapplication_name,SUM(EXTRACT(EPOCH FROM (CURRENT_TIMESTAMP - state_change))::bigint)::float AS process_idle_seconds_sum,COUNT(*) AS process_idle_seconds_countFROM pg_stat_activityWHERE state = 'idle'GROUP BY application_name),buckets AS (SELECTapplication_name,le,SUM(CASE WHEN EXTRACT(EPOCH FROM (CURRENT_TIMESTAMP - state_change)) <= leTHEN 1ELSE 0END)::bigint AS bucketFROMpg_stat_activity,UNNEST(ARRAY[1, 2, 5, 15, 30, 60, 90, 120, 300]) AS leGROUP BY application_name, leORDER BY application_name, le)SELECTapplication_name,process_idle_seconds_sum as seconds_sum,process_idle_seconds_count as seconds_count,ARRAY_AGG(le) AS seconds,ARRAY_AGG(bucket) AS seconds_bucketFROM metrics JOIN buckets USING (application_name)GROUP BY 1, 2, 3metrics:- application_name:usage: "LABEL"description: "Application Name"- seconds:usage: "HISTOGRAM"description: "Idle time of server processes"

三、PostgreSQL数据库配置

1. 修改postgresql.conf配置文件

1. 先根据命令在服务器上找到配置文件在哪

find / -name postgresql.conf

2. 修改配置文件postgresql.conf，添加下面三行

shared_preload_libraries = 'pg_stat_statements'      
pg_stat_statements.max = 1000
pg_stat_statements.track = all

3. 重启pg服务（pg不同安装方式启动方式可能不同）

pg_ctl restart

2. 创建用户、表、扩展等

官网的文档里提示比pg10高或低版本的数据库执行的SQL不同，但是我pg11只执行高版本的SQL失败了。最终高低版本都执行成功。

最好在postgres库下的public模式执行

版本>=10的pg，以下三段SQL都要执行

-- To use IF statements, hence to be able to check if the user exists before
-- attempting creation, we need to switch to procedural SQL (PL/pgSQL)
-- instead of standard SQL.
-- More: https://www.postgresql.org/docs/9.3/plpgsql-overview.html
-- To preserve compatibility with <9.0, DO blocks are not used; instead,
-- a function is created and dropped.
CREATE OR REPLACE FUNCTION __tmp_create_user() returns void as $$
BEGINIF NOT EXISTS (SELECT                       -- SELECT list can stay empty for thisFROM   pg_catalog.pg_userWHERE  usename = 'postgres_exporter') THENCREATE USER postgres_exporter;END IF;
END;
$$ language plpgsql;SELECT __tmp_create_user();
DROP FUNCTION __tmp_create_user();ALTER USER postgres_exporter WITH PASSWORD 'password';
ALTER USER postgres_exporter SET SEARCH_PATH TO postgres_exporter,pg_catalog;-- If deploying as non-superuser (for example in AWS RDS), uncomment the GRANT
-- line below and replace <MASTER_USER> with your root user.
-- GRANT postgres_exporter TO <MASTER_USER>;GRANT CONNECT ON DATABASE postgres TO postgres_exporter;

GRANT pg_monitor to postgres_exporter;

版本<10的pg，只执行下面的SQL

CREATE SCHEMA IF NOT EXISTS postgres_exporter;
GRANT USAGE ON SCHEMA postgres_exporter TO postgres_exporter;CREATE OR REPLACE FUNCTION get_pg_stat_activity() RETURNS SETOF pg_stat_activity AS
$$ SELECT * FROM pg_catalog.pg_stat_activity; $$
LANGUAGE sql
VOLATILE
SECURITY DEFINER;CREATE OR REPLACE VIEW postgres_exporter.pg_stat_activity
ASSELECT * from get_pg_stat_activity();GRANT SELECT ON postgres_exporter.pg_stat_activity TO postgres_exporter;CREATE OR REPLACE FUNCTION get_pg_stat_replication() RETURNS SETOF pg_stat_replication AS
$$ SELECT * FROM pg_catalog.pg_stat_replication; $$
LANGUAGE sql
VOLATILE
SECURITY DEFINER;CREATE OR REPLACE VIEW postgres_exporter.pg_stat_replication
ASSELECT * FROM get_pg_stat_replication();GRANT SELECT ON postgres_exporter.pg_stat_replication TO postgres_exporter;CREATE EXTENSION IF NOT EXISTS pg_stat_statements;
CREATE OR REPLACE FUNCTION get_pg_stat_statements() RETURNS SETOF pg_stat_statements AS
$$ SELECT * FROM public.pg_stat_statements; $$
LANGUAGE sql
VOLATILE
SECURITY DEFINER;CREATE OR REPLACE VIEW postgres_exporter.pg_stat_statements
ASSELECT * FROM get_pg_stat_statements();GRANT SELECT ON postgres_exporter.pg_stat_statements TO postgres_exporter;

来到postgres_exporter安装目录，启动postgres_exporter

sh start.sh

观察nohup.out文件，看是否有报错信息。

如果集成了Grafana，可以发现页面已经能采集到数据了

Grafana+prometheus+postgres_exporter参考

四、参考

• Github地址
• postgres_exporter使用过程中的注意事项