Category: Thread

Physical replication relies on the concept of streaming WAL segments from primary node to a replica node. The replica is in the state of continuous recovery – it continuously execute WAL segments received from primary node.In Synchronous replication primary node ensures replica received WAL segments before completion, while in asynchronous mode WAL segments are streamed…

I was mainly writing down notes about Postgres configuration. I have started reading about physical replication but I will include the notes about this chapter later.

I completed the configuration & monitoring chapter. Postgres allows configuration modifications while cluster runs by means of ALTER SYSTEM command. Modifications applied this way will be appended to postgresql.auto.conf file.You can use configuration generators like PgConfig with simple GUI interface.Information about running queries, sessions and backend processes can be read from pg_stat_activity catalog. Information about…

[Book “Learn PostgreSQL”] Postgres stores configuration across several files – posgresql.conf, postgressql.auto.conf and pg_hba.conf. You can extend settings with additional configuration files, this allows to organize settings by topic – use include_file, include_dir or include_if_exists directives. You can inspect settings using SHOW command or by querying pg_setting catalog.Each configuration belongs to a context which defines…

[Book “Learn PostgreSQL”] I completed the chapter about physical backups. They are performed by coping PGDATA, tablespaces and WALs to another machine or different directory. You can leverage a buid-in postgres command pg_basebackup or 3rd party tool pgBackRest. Physical backups require careful approach to configuration e.g. connections values and hba rules. Point in time recovery is…