omacchioni / snmp_psql_performance

Export of PostgreSQL performance metrics via SNMP

Introduction

This program allows to export statistics of all the databases of your PostgreSQL cluster via SNMP. Those statistics can then be easily monitored or graphed via all the "usual" SNMP-based tools.

The statistics are gathered from the pg_stat_database table, and then exported using NET-SNMP's pass_persist directive.

Installation

The script sould probably be installed on the PostgreSQL server itself (although it could be running on any server which can connect to the database).

It requires a valid user which can do a select on the pg_stat_database table.

Prerequisites

Use pip to get the following packages:

• psycopg2
• snmp_passpersist
• argparse

sudo pip install psycopg2 snmp_passpersist argparse

Checking

Check that the script runs correctly by launching it manually:

./snmp_psql_performance.py -U USER -W PASSWORD

The program should start. By typing DUMP<CR>, you should see a long list of OIDS similar to this one:

{'1.1.1.1': {'type': 'STRING', 'value': '1'},
 '1.1.1.10': {'type': 'Counter32', 'value': '0'},
 '1.1.1.11': {'type': 'Counter32', 'value': '2'},
 '1.1.1.12': {'type': 'Counter32', 'value': '0'},
 '1.1.1.13': {'type': 'Counter32', 'value': '0'},
 '1.1.1.19': {'type': 'TIMETICKS', 'value': '19'},
 '1.1.1.2': {'type': 'STRING', 'value': 'template1'},
 '1.1.1.3': {'type': 'GAUGE', 'value': '0'},

If this doesn't work, check the logs (probably in /var/log/messages , depending on your Syslog configuration)

Configuring NET-SNMP

Add the following line to /etc/snmp/snmpd.conf:

pass_persist .1.3.6.1.4.1.42916 /path/to/snmp_psql_performance.py -U USER -W PASSWORD

And restart snmpd:

sudo /etc/init.d/snmpd restart

Check the outcome by doing a direct SNMP request:

snmpwalk -Cc -v 1 -c public localhost .1.3.6.1.4.1.42916

You should see something similar to this:

iso.3.6.1.4.1.42916.1.1.1.1 = STRING: "1"
iso.3.6.1.4.1.42916.1.1.1.2 = STRING: "template1"
iso.3.6.1.4.1.42916.1.1.1.3 = Gauge32: 0
iso.3.6.1.4.1.42916.1.1.1.4 = Counter32: 33
iso.3.6.1.4.1.42916.1.1.1.5 = Counter32: 2
iso.3.6.1.4.1.42916.1.1.1.6 = Counter32: 10
iso.3.6.1.4.1.42916.1.1.1.7 = Counter32: 7
iso.3.6.1.4.1.42916.1.1.1.8 = Counter32: 28
iso.3.6.1.4.1.42916.1.1.1.9 = Counter32: 21
iso.3.6.1.4.1.42916.1.1.1.10 = Counter32: 0
iso.3.6.1.4.1.42916.1.1.1.11 = Counter32: 2

The list of OIDs returned is described at the beginning of the source code of the file.

TODO

• Be compatible with all versions of PostgreSQL (the content of pg_stat_database is not always the same)
• Get an own OID identifier
• Export more data ?
• Write the MIB file to make the SNMP output nicer to read