H.7. slru_upgrader#

H.7. slru_upgrader

H.7. slru_upgrader
Prev	Up	Appendix H. Additional Supplied Utilities	Home	Next

H.7. slru_upgrader #

H.7.1. Overview
H.7.2. Synopsis
H.7.3. Environment
H.7.4. Usage
H.7.5. Notes
H.7.6. Exit Status

H.7.1. Overview #

Starting with Tantor SE version 16, several configuration parameters that control buffer allocation for the Simple Least Recently Used (SLRU) mechanism were renamed. When the postgresql.conf file contains old parameter names, the server will fail to start after upgrading to version 16.

upgrade-SLRU-from-TT_15-to-TT_16-version.sh automates the migration of these parameters renaming them in the postgresql.conf file in place located in the data directory specified by the PGDATA environment variable.

The following parameter names have been updated:

Old Name (Tantor SE 15)	New Name (Tantor SE 16)
`commit_ts_buffers`	`commit_timestamp_buffers`
`serial_buffers`	`serializable_buffers`
`subtrans_buffers`	`subtransaction_buffers`
`xact_buffers`	`transaction_buffers`

Before modifying the configuration file, the script creates a backup copy in $PGDATA/postgresql.conf.bak. It is recommended to verify the updated configuration and remove the backup once the server starts correctly.

H.7.2. Synopsis #

PGDATA='/path/to/data'
/opt/tantor/db/17/tools/slru_upgrader/upgrade-SLRU-from-TT_15-to-TT_16-version.sh [option]

H.7.2.1. Options #

--help: Display usage information and exit.

H.7.3. Environment #

PGDATA: Specifies the path to the Tantor SE data directory that contains postgresql.conf. This variable must be set before running the script.

H.7.4. Usage #

Typical usage during a major version upgrade from Tantor SE 15 to 17:

Stop the database server running Tantor SE 15.
Set the PGDATA environment variable to point to the data directory that will be used by Tantor SE 17:
```
export PGDATA='/var/lib/postgresql/tantor-se-17/data'
```

Run the upgrade script:

/opt/tantor/db/17/tools/slru_upgrader/upgrade-SLRU-from-TT_15-to-TT_16-version.sh

Start the Tantor SE 17 server and verify that it operates correctly.
Once the configuration has been verified, remove the backup:
```
rm "$PGDATA/postgresql.conf.bak"
```

H.7.5. Notes #

The script exits immediately if any command fails (set -e).
If a parameter is not present in postgresql.conf, it is silently skipped.
Leading whitespace before parameter names is handled correctly; however, lines that are commented out (prefixed with #) are not modified.
The script does not validate parameter values — only the parameter names are renamed.

H.7.6. Exit Status #

0 — the configuration file was successfully updated (or no matching parameters were found).

1 — an error occurred. Possible causes include:

PGDATA is not set.
postgresql.conf does not exist in the specified data directory.
An unknown command-line option was provided.

Prev	Up	Next
H.6. pgcopydb	Home	Appendix I. Tantor Additional Programs Distributed as Separate Packages