pgadmin4/docs/en_US/maintenance_dialog.rst
Akshay Joshi a460644ae8
1) Added support for SYSTEM, CONCURRENTLY and TABLESPACE options in REINDEX. #6381
2) Added new/missing options to the VACUUM command. #6397
3) Added SKIP_LOCKED and BUFFER_USAGE_LIMIT option to Analyze command. #6415
2023-07-27 17:34:25 +05:30

124 lines
5.3 KiB
ReStructuredText

.. _maintenance_dialog:
***************************
`Maintenance Dialog`:index:
***************************
Use the *Maintenance* dialog to VACUUM, ANALYZE, REINDEX or CLUSTER a database
or selected database objects.
While this utility is useful for ad-hoc maintenance purposes, you are encouraged
to perform automatic VACUUM jobs on a regular schedule.
Select a button next to *Maintenance operation* to specify the type of
maintenance:
.. image:: images/maintenance_vacuum.png
:alt: Maintenance dialog
:align: center
* Click *VACUUM* to scan the selected database or table to reclaim storage used
by dead tuples.
* Move the *FULL* switch to the *Yes* position to compact tables by writing
a completely new version of the table file without dead space.
* Move the *FREEZE* switch to the *Yes* position to freeze data in a table
when it will have no further updates.
* Move the *ANALYZE* switch to the *Yes* position to issue ANALYZE commands
whenever the content of a table has changed sufficiently.
* Move the *DISABLE PAGE SKIPPING* switch to the *Yes* position to disables
all page-skipping behavior.
* Move the *SKIP LOCKED* switch to the *Yes* position to specifies that
VACUUM should not wait for any conflicting locks to be released when
beginning work on a relation. This option is available from v12 onwards.
* Move the *TRUNCATE* switch to the *Yes* position to specifies that VACUUM
should attempt to truncate off any empty pages at the end of the table and
allow the disk space for the truncated pages to be returned to the operating
system. This option is available from v12 onwards.
* Move the *PROCESS TOAST* switch to the *Yes* position to specifies that
VACUUM should attempt to process the corresponding TOAST table for each
relation, if one exists. This option is available from v14 onwards.
* Move the *PROCESS MAIN* switch to the *Yes* position to specifies that
VACUUM should attempt to process the main relation. This option is available
from v16 onwards.
* Move the *SKIP DATABASE STATS* switch to the *Yes* position to specifies
that VACUUM should skip updating the database-wide statistics about oldest
unfrozen XIDs. This option is available from v16 onwards.
* Move the *ONLY DATABASE STATS* switch to the *Yes* position to specifies
that VACUUM should do nothing except update the database-wide statistics
about oldest unfrozen XIDs . This option is available from v16 onwards.
* Use the *INDEX CLEANUP* field to force VACUUM to process indexes when there
are more than zero dead tuples.
* Use the *PARALLEL* field to specify index vacuum and index cleanup phases
of VACUUM in parallel using integer background workers. This option is
available from v13 onwards.
* Use the *BUFFER USAGE LIMIT* field to specifies the Buffer Access Strategy
ring buffer size for VACUUM. This size is used to calculate the number of
shared buffers which will be reused as part of this strategy. This option
is available from v16 onwards
.. image:: images/maintenance_analyze.png
:alt: Maintenance dialog
:align: center
* Click *ANALYZE* to update the stored statistics used by the query planner.
This enables the query optimizer to select the fastest query plan for optimal
performance.
* Move the *SKIP LOCKED* switch to the *Yes* position to specifies that
ANALYZE should not wait for any conflicting locks to be released when
beginning work on a relation. This option is available from v12 onwards.
* Use the *BUFFER USAGE LIMIT* field to specifies the Buffer Access Strategy
ring buffer size for ANALYZE. This size is used to calculate the number of
shared buffers which will be reused as part of this strategy. This option
is available from v16 onwards
.. image:: images/maintenance_reindex.png
:alt: Maintenance dialog
:align: center
* Click *REINDEX* to rebuild any index in case it has degenerated due to the
insertion of unusual data patterns. This happens, for example, if you insert
rows with increasing index values, and delete low index values.
* Move the *SYSTEM* switch to the *Yes* position to recreate all indexes
on system catalogs within the current database. This option is enabled
only when database object is selected.
* Move the *CONCURRENTLY* switch to the *Yes* position to rebuild the index
without taking any locks that prevent concurrent inserts, updates, or
deletes on the table. This option is available from v12 onwards.
* Use the *TABLESPACE* field to specifies that indexes will be rebuilt on
a new tablespace. This option is available from v14 onwards.
.. image:: images/maintenance_cluster.png
:alt: Maintenance dialog
:align: center
* Click *CLUSTER* to instruct PostgreSQL to cluster the selected table.
To exclude status messages from the process output, move the *Verbose Messages*
switch to the *No* position; by default, status messages are included.
When you've completed the dialog, click *OK* to start the background process;
to exit the dialog without performing maintenance operations, click *Cancel*.
pgAdmin will run the maintenance process in background. You can view all the background
process with there running status and logs on the :ref:`Processes <processes>`
tab.