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Short Description

Waiting to read or update the control file or creation of a new WAL file.

Detailed Description

This wait is removed from PostgreSQL v13 onwards.

The control file pg_control is an 8kb binary file which stores information about various aspects of the PostgreSQL server's internal state, such as the most recent checkpoint, as well as fundamental parameters set by initdb. It is located in the cluster's global/ directory.

How to reduce this wait

Updating the control file is fundamental to the normal operation of the database.

Ensure the server I/O subsystem is performing correctly across the cluster.

PostgreSQL Docs - Wait Events of Type IO

pgpedia - pg_control

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