prometheus|云原生|prometheus项目安装postgres-exporter监视组件的部署简介

DATA_SOURCE_NAME=postgresql://localhost:数据库端口/postgres?sslmode=disable

cat > /usr/lib/systemd/system/postgres_exporter.service<<EOF
[Unit]
Description=postgres_exporter
After=network.target
[Service]
Type=simple
User=postgres
Environment="DATA_SOURCE_NAME=postgresql//:localhost@数据库ip:数据库端口/postgres?sslmode=disable"
ExecStart=/usr/local/bin/postgres_exporter --log.level=error --web.listen-address=:9187
Restart=on-failure
[Install]
WantedBy=multi-user.target
EOF

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: true
  metrics:
    - 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: true
  metrics:
    - start_time_seconds:
        usage: "GAUGE"
        description: "Time at which postmaster started"
pg_stat_user_tables:
  query: |
   SELECT
     current_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_count
   FROM
     pg_stat_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"
    - 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: true
  metrics:
    - 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: |
    WITH
      metrics AS (
        SELECT
          application_name,
          SUM(EXTRACT(EPOCH FROM (CURRENT_TIMESTAMP - state_change))::bigint)::float AS process_idle_seconds_sum,
          COUNT(*) AS process_idle_seconds_count
        FROM pg_stat_activity
        WHERE state = 'idle'
        GROUP BY application_name
      ),
      buckets AS (
        SELECT
          application_name,
          le,
          SUM(
            CASE WHEN EXTRACT(EPOCH FROM (CURRENT_TIMESTAMP - state_change)) <= le
              THEN 1
              ELSE 0
            END
          )::bigint AS bucket
        FROM
          pg_stat_activity,
          UNNEST(ARRAY[1, 2, 5, 15, 30, 60, 90, 120, 300]) AS le
        GROUP BY application_name, le
        ORDER BY application_name, le
      )
    SELECT
      application_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_bucket
    FROM metrics JOIN buckets USING (application_name)
    GROUP BY 1, 2, 3
  metrics:
    - application_name:
        usage: "LABEL"
        description: "Application Name"
    - seconds:
        usage: "HISTOGRAM"
        description: "Idle time of server processes"

添加配置Prometheus文件
- job_name: 'postgres_exporter'
    scrape_interval: 1s
    file_sd_configs:
      - files:
        - targets/postgresql/*.yml
        refresh_interval: 10s
    relabel_configs:
    - action: replace
      source_labels: ['__address__']
      regex: (.*):(.*)
      replacement: $1
      target_label: hostname
    - action: labeldrop
      regex: __meta_filepath
添加监控对象
vi targets/postgresql/pg1-instance.yml
[
  {
    "targets": ["localhost:9187"],
    "labels": { "instance": 'postgres:5432' }
  }
]

版本>=10的pg，以下三段SQL都要执行
CREATE OR REPLACE FUNCTION __tmp_create_user() returns void as $$
BEGIN
  IF NOT EXISTS (
          SELECT                       -- SELECT list can stay empty for this
          FROM   pg_catalog.pg_user
          WHERE  usename = 'postgres_exporter') THEN
    CREATE USER postgres_exporter;
  END IF;
END;
$$ 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
AS
  SELECT * 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
AS
  SELECT * 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
AS
  SELECT * FROM get_pg_stat_statements();