This is a set of updates for collectd to collect data from Postgres.
| The file | Description |
|---|---|
| etc/conf.d/postgresql.conf | SCHARP Postgres Configuration |
| collectd/types.postgres.db | SCHARP Postgres Types |
| etc/collectd.conf | Collectd Configuration (Edited) |
| collectd/postgresql_default.conf | Default Postgres Configuration (Default) |
| collectd/types.db | Default Types including Postgres (Default) |
To install this, just copy the first two files into your collectd installation. The third file is already part of your collectd installation and just needs to be edited to a TypedDB line for the types.postgres.db file and a Include line for the postgresql.conf file as shown in the example collectd.conf file. The last two files are already part of your collectd installation.
You will want to edit the end of the postgresql.conf file to add a Database section for each of your servers and sometimes spevialized ones for specific databases.
<Database postgres>
Instance "db-a"
Host "db-a"
Port "5432"
User "postgres"
Query connections
Query connection_states
Query connection_state
Query database_size
Query buffercache
Query buffercache_databases
Query database_transactions
Query transactions
Query concurrent_txns
Query pg_hit_ratio
Query pg_xlog
Query connection_state_by_database
Query database_commit_ratio_by_database
Query database_stats_by_database
Query query_length
Query query_length_server
Query wait_length
Query wait_length_server
Query transaction_length
Query transaction_length_server
</Database>Use the Stats for Standalone Server and add the following lines
Query a_server_locationUse the Stats for Standalone Server and add the following lines
Query b_server_location
Query pg_conflicts#Stats for a specific database
<Database main>
Instance "main"
Host "db-a"
Port "5432"
User "postgres"
Query pg_trig_disabled
</Database> <Database main>
Instance "main"
Host "sqltest"
Port "5432"
User "postgres"
Query stat_tables
Query planning_time
Interval 300
</Database>The use of stat_tables and planning_time requires editing these sections to your needs.
You only need this is you want this information for a specific table, otherwise you can use the following queries out of the postgresql_default.conf file. The only things not covered by the default is the autovacuum and analyze portions of the stat_tables.
- queries_by_table
- query_plans_by_table
- table_states_by_table
You need to edit the query and add the table names, in two places, that you wish to capature the stats, for both the main table and the toast table.
<Query stat_tables>
Statement "SELECT
b.schemaname || '_' || b.relname AS table,
b.seq_scan,
b.seq_tup_read,
b.idx_scan,
b.idx_tup_fetch,
b.n_tup_ins,
b.n_tup_upd,
b.n_tup_del,
b.n_tup_hot_upd,
b.n_live_tup,
b.n_dead_tup,
b.n_mod_since_analyze,
b.vacuum_count,
b.autovacuum_count,
b.analyze_count,
b.autoanalyze_count
FROM pg_stat_all_tables b
WHERE relname IN ('table_name')
UNION ALL
SELECT
b.schemaname || '_pg_toast_' || a.relname AS table,
b.seq_scan,
b.seq_tup_read,
b.idx_scan,
b.idx_tup_fetch,
b.n_tup_ins,
b.n_tup_upd,
b.n_tup_del,
b.n_tup_hot_upd,
b.n_live_tup,
b.n_dead_tup,
b.n_mod_since_analyze,
b.vacuum_count,
b.autovacuum_count,
b.analyze_count,
b.autoanalyze_count
FROM pg_class a
LEFT JOIN pg_stat_all_tables b ON b.relname = 'pg_toast_' || a.oid
WHERE a.relname IN ('table_name');"
<Result>
Type pg_stat_tables
InstancesFrom "table"
ValuesFrom 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,vacuum_count,autovacuum_count,analyze_count, autoanalyze_count
</Result>
</Query>Note: I need to update this query for you to be able to specify schema. The current queries limited by the fact that all tables with the same name will be reported back no matter which schema they are found.
In this example I am testing the planning time of quering pg_roles. This is sendign an array of arrays to the planning_time functions, this means that you can test several queries at once within the same transaction block / data snapshot.
<Query planning_time>
Statement "SELECT * FROM ds.planning_time(ARRAY[
ARRAY['pg_roles', E'SELECT * FROM pg_roles']
]);"
<Result>
Type pg_planning_time
InstancesFrom "query"
ValuesFrom planning_time
</Result>
</Query> <Database postgres>
Instance "db-a"
Host "db-a"
Port "5432"
User "postgres"
Query connections
Query connection_states_96
Query connection_state_96
Query database_size
Query buffercache
Query buffercache_databases
Query database_transactions
Query transactions
Query concurrent_txns_96
Query pg_hit_ratio
Query pg_xlog_96
Query connection_state_by_database_96
Query database_commit_ratio_by_database
Query database_stats_by_database
Query query_length
Query query_length_server
Query wait_length_96
Query wait_length_server_96
Query transaction_length
Query transaction_length_server
Query autovacuums_96
Query autovacuums_server_96
Query transaction_length_10
Query autovacuum_length_server_10
</Database>Use the Stats for Standalone Server and add the following lines
Query a_server_location_96Use the Stats for Standalone Server and add the following lines
Query b_server_location_96
Query pg_conflictsMy recomendation if you are running both a primary and secondary server is to add the stats for primary and secondary to the both servers for when you swap the two servers.
NOTE: The planning_time requires the planning time function from my SCHARP-PG-DBA-Tools toolset.