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You probably have noticed already that Odoobravo and PostgreSQL are installed in separate packages. That should give you the following clue:

The standard PostgreSQL installation is neither optimized for your hardware not for your Odoo

Before you move into running PostgreSQL with your Odoo and through Python-driven requests, here is a list of the things you should do to give your system a real chance to run decently:

PostgreSQL logging

  • Be generous with logging; it’s very low-impact on the system

  • Locations for logs are better managed by syslog.

  • Just use:

log_destination = ‘csvlog’

log_directory = ‘pg_log’



  • Start low: 32-64MB

  • Look for ‘temporary file’ lines in logs

  • set to 2-3x the largest temp file you see

  • Can cause a huge speed-up if set properly

  • Be careful: it can use that amount of memory per query


  • Set to 10% of system memory, up to 1GB


  • Set to the amount of file system cache available

  • If you don’t know it, set it to 50% of the available memory


  • A complete fish of dirty buffers to disk

  • Potentially a lot of I/O

Easy performance boosts

  • Don’t run anything else on your PostgreSQL server

  • If PostgreSQL is in a VM, remember all of the other VMs on the same host

  • Disable the Linux OOM killer

Stupid Database Tricks

  • Don’t put your sessions in the database

  • Avoid aonstantly-updated accumulator records.

  • Don’t put the task queues in the database

  • Don’t use the database as a filesystem

  • Don’t use frequently-locked singleton records

  • Don’t use very long-running transactions

  • Mixing transactional and data warehouse queries on the same database

One schema trick

  • If one model ha sa constantly-updated section and a rarely-updated section

  • last-seen on site field

  • cut out that field into a new model

SQL Pathologies

  • Gigantic IN clauses (a typical Django anti-pattern) are problematic

  • Unanchored text queries like ‘%this%’ run slow


  • A good index has high selectivity on commonly-used data and will return a small number of records

  • A good infex is determined by analysis, not guessing

  • Use pg_stat_user_tables – shows sequential scans

  • Use pg_stat_index_blah


  • autovacuum slowing the system down? Increase autovacuum_vacuum_cost_limit in small increments

  • If the load is periodic, do manual VACUUMing instead at low-low times

  • You must VACUUM on a regular basis

  • Analyze your vacuum

  • Collect statistics on the data to help the planner choose a good plan

On-going maintenance and monitoring

  • Keep track of disk space and system load

  • memory and I/O utilization is very handy

  • 1 minute bnts

  • at

2 different orientation for Backups


  • Easiest backup tool for PostgreSQL

  • Low impact on a running database

  • Makes a copy of the database

  • becomes impractical for large databases

Streaming replication

  • Best solution for large databases

  • Easy to set up

  • Maintains an exact logical copy of the database on a different host

  • Does not guard against application-level failures, however

  • Can be used for read-only queries

  • if you are getting query cancellations then bump up a config

  • Is all-or-nothing

  • If you need partial replication, you need to use Slony or Bucardo

  • ..warning:: partial replication is a full-time effort

WAL Archiving

  • Maintains a set of base backups and WAL segments on a remote server

  • Can be used for point-in-time recovery in case of an application (or DBA) failure

  • Slightly more complex to set up


  • Character encoding is fixed in a database when created

  • The defaults are not what you want

  • Use UTF-8 encoding


  • All modifications to a table take an exclusive lock on that table while the modification is being done.

  • If you add a column with a default value, the table will be rewritten

  • Migrating a big table

  • Create the column as NOT NULL

  • Add constraint later once field is populated

  • Note


  • Once in a while PostgreSQL needs to scan every table

  • THis can be a very big surprise

  • Run VACUUM manually periodically


  • Get lots of ECC RAM

  • CPU is not as vital as RAM

  • Use a RAID