Solving the create publication Command Issue in PostgreSQL 14 After Upgrade

Discover how to troubleshoot and resolve the `create publication` command being stuck in PostgreSQL 14 after a database upgrade, and ensure optimal database health with effective vacuuming strategies.
---
This video is based on the question https://stackoverflow.com/q/70264036/ asked by the user 'nullptr' ( https://stackoverflow.com/u/3550139/ ) and on the answer https://stackoverflow.com/a/70264642/ provided by the user 'Laurenz Albe' ( https://stackoverflow.com/u/6464308/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: postgres 14 "create publication" stuck for hours

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Troubleshooting Stuck create publication Command in PostgreSQL 14

Upgrading databases can often introduce complications, particularly with backend processes that manage data integrity and performance. Many users migrating from older versions of PostgreSQL, such as version 10 to version 14, find themselves facing unexpected issues. A notable problem arises when commands like create publication become unresponsive. In this guide, we will explore the cause of this issue and provide methods to resolve it.

Understanding the Problem

If you recently upgraded your PostgreSQL server using pg_upgrade and encountered an unresponsive create publication command, you are not alone. As noted in a common scenario, running the vacuumdb --all --analyze-in-stages command can lead to a vacuum process that seems stuck. As observed, this may result in uncompleted tasks and lengthy wait times, causing frustration and delay in your database performance.

Symptoms of the Issue

Unresponsive Command: The create publication command does not return control after several hours.

Stuck Vacuum Process: Queries show that a vacuum process is running without making progress.

Database Activity Monitoring: Views like pg_stat_activity indicate that the current state is waiting, specifically for VacuumDelay.

Understanding these symptoms is the first step toward resolving the issue.

Analyzing Your Database State

To diagnose what is happening under the hood, utilize the following PostgreSQL views:

pg_stat_progress_vacuum: Shows the current progress of vacuum tasks.

pg_stat_activity: Reveals active database processes and their states.

By running SELECT * FROM pg_stat_progress_vacuum;, you can see metrics regarding the vacuuming status. For example, in your case, the output revealed:

The process was stuck on "vacuuming indexes."

A high number of dead tuples requiring attention.

The Solution Explained

Understanding vacuumdb vs VACUUM

It is crucial to understand that running the command vacuumdb --all --analyze-in-stages effectively executes ANALYZE on tables but does not run an actual VACUUM operation. This means the vacuum process you see may serve different purposes, and understanding the distinction is essential for proper database management.

Important Notes:

The VACUUM process is essential to prevent transaction ID wraparound, particularly in large databases. It should not be interrupted.

Let If Finish: Be patient; allow the vacuum process to complete. This is critical for the health of your database.

Speeding Up AUTOVACUUM

If you find the autovacuum processes sluggish and wish to expedite the completion of tasks, consider adjusting the autovacuum_vacuum_cost_delay parameter for your database. A lower value can lead to faster overall processing. However, apply such changes judiciously to avoid putting undue stress on the server.

Final Thoughts

If you are facing prolonged pauses when executing commands after an upgrade in PostgreSQL, take heart that this issue often resolves itself with appropriate management. Ensure your vacuum processes are allowed to complete, and consider optimizing autovacuum settings where feasible.

By following the outlined strategies, you should be able to restore normal function to your create publication command and maintain a healthier database environment moving forward.

For more troubleshooting tips or inquiries on PostgreSQL configurations, feel free to reach out!