19.7. The Engine Vacuum Tool


19.7.1. The Engine Vacuum Tool

The Engine Vacuum tool maintains PostgreSQL databases by updating tables and removing dead rows, allowing disk space to be reused. See the PostgreSQL documentation for information about the VACUUM command and its parameters.
The Engine Vacuum command is engine-vacuum. You are required to log in as the root user and provide the administration credentials for the Red Hat Virtualization environment.
Alternatively, the Engine Vacuum tool can be run while using the engine-setup command to customize an existing installation:
$ engine-setup
...
[ INFO  ] Stage: Environment customization
...
Perform full vacuum on the engine database engine@localhost?
This operation may take a while depending on this setup health and the
configuration of the db vacuum process.
See https://www.postgresql.org/docs/9.2/static/sql-vacuum.html
(Yes, No) [No]:
Copy to Clipboard Toggle word wrap
The Yes option runs the Engine Vacuum tool in full vacuum verbose mode.

19.7.2. Engine Vacuum Modes

Engine Vacuum runs in two modes, Standard and Full.

Standard Vacuum

Frequent standard vacuuming is recommended.
Standard vacuum removes dead row versions in tables and indexes and marks the space as available for future reuse. Frequently updated tables should be vacuumed on a regular basis. However, standard vacuum does not return the space to the operating system.
Standard vacuum, with no parameters, processes every table in the current database.

Full Vacuum

Full vacuum is not recommended for routine use, but should only be run when a significant amount of space needs to be reclaimed from within the table.
Full vacuum compacts the tables by writing a new copy of the table file with no dead space, thereby enabling the operating system to reclaim the space. Full vacuum can take a long time.
Full vacuum requires extra disk space for the new copy of the table, until the operation completes and the old copy is deleted. Because full vacuum requires an exclusive lock on the table, it cannot be run in parallel with other uses of the table.

19.7.3. Syntax for the Engine Vacuum

The basic syntax for the Engine Vacuum command is:
engine-vacuum
Copy to Clipboard Toggle word wrap
engine-vacuum [option]
Copy to Clipboard Toggle word wrap
Running the engine-vacuum command with no options performs a standard vacuum.
There are several parameters to further refine the engine-vacuum command.

General Options

-h --help
Displays information on how to use the engine-vacuum command.
-a
Runs a standard vacuum, analyzes the database, and updates the optimizer statistics.
-A
Analyzes the database and updates the optimizer statistics, without vacuuming.
-f
Runs a full vacuum.
-v
Runs in verbose mode, providing more console output.
-t [table_name]
Vacuums a specific table or tables.
engine-vacuum -f -v -t vm_dynamic -t vds_dynamic
Copy to Clipboard Toggle word wrap
Red Hat logoGithubredditYoutubeTwitter

詳細情報

試用、購入および販売

コミュニティー

Red Hat ドキュメントについて

Red Hat をお使いのお客様が、信頼できるコンテンツが含まれている製品やサービスを活用することで、イノベーションを行い、目標を達成できるようにします。 最新の更新を見る.

多様性を受け入れるオープンソースの強化

Red Hat では、コード、ドキュメント、Web プロパティーにおける配慮に欠ける用語の置き換えに取り組んでいます。このような変更は、段階的に実施される予定です。詳細情報: Red Hat ブログ.

会社概要

Red Hat は、企業がコアとなるデータセンターからネットワークエッジに至るまで、各種プラットフォームや環境全体で作業を簡素化できるように、強化されたソリューションを提供しています。

Theme

© 2026 Red Hat
トップに戻る