E.17. Release Notes for Tantor BE 15.2.0#
E.17. Release Notes for Tantor BE 15.2.0
Release date: 2023-06-01
E.17.1. Review
Tantor BE is a Russian-made DBMS based on the updated and improved version of the PostgreSQL DBMS. Tantor BE 15.2.0 is based on PostgreSQL 15.
Below are the additional modules and utilities added to Tantor BE, as well as a list of changes to the server core.
E.17.2. Significant differences in this version
E.17.2.1. Reserving connections
Added ability to reserve connection slots for users that do not have superuser rights.
Connections are reserved via the new configuration parameter reserved_connections (in the postgresql.conf file), and are only available to users with the new predefined role pg_use_reserved_connections.
The value of the superuser_reserved_connections parameter remains as a final reserve in case reserved_connections have been exhausted.
- reserved_connections details:
E.17.2.2. Added transaction_timeout parameter
The transaction_timeout parameter allows you to cancel any transaction that lasts longer than the specified time period. The limit applies to both explicit transactions (started with the BEGIN command) and implicitly started transactions corresponding to an individual statement.
- transaction_timeout details:
E.17.2.3. Prefetching blocks for the prefetching log (WAL)
Improves performance by pre-reading Tantor BE log blocks (WAL blocks) using the posix_fadvise() system call with the POSIX_FADV_WILLNEED parameter.
Added new WAIT_EVENT_WAL_PREFETCH event to track the time it takes to pre-read the WAL.
E.17.3. Additional modules and utilities available
E.17.3.1. Modules added in the current release
Table E.1. Table of extensions
| Extension | Description |
|---|---|
| page_repair | A module for recovering individual damaged pages using data from the hot standby server. Allows you to save recovery time because it does not require recovery of all data, but only individual pages. |
| pg_background | The module allows the user to execute an arbitrary command in the background and gives users the ability to run commands such as: VACUUM and CREATE INDEX CONCURRENTLY from SQL, as well as run offline transactions, including asynchronous mode. |
| pg_repack | The module allows you to eliminate the bloat of tables and indexes (bloat) and, if necessary, restore the physical order of clustered indexes (CLUSTER). Unlike CLUSTER and VACUUM FULL commands, it works online without holding the exclusive lock of the tables being served during operation. |
E.17.3.2. Additional supplied programs
Table E.2. Table of utilities
| Utility | Description |
|---|---|
pgcompacttable
| pgcompacttable is a tool to reduce the size of bloated tables and indexes (bloat) without heavy blocking. It is designed to reorganize data in tables and rebuild indexes to regain disk space without affecting database performance. |
E.17.4. Supported Operating Systems
The list of supported operating systems (OS) has been expanded. The full list is provided below:
Altlinux c9f2 (P8)
Altlinux p10
Astra Linux Common Edition 2.12
Astra Linux Special Edition 1.7
Astra Linux Special Edition 4.7
Redos 7.3
MSVSphere
Centos 7
Rocky 8
Rocky 9
Ubuntu 18
Ubuntu 20
Ubuntu 22
Debian 11 Bullseye
Debian 10 Buster
DBMS builds are created and tested for these operating systems on an ongoing basis.
E.17.5. Migration to version 15.2.0
To migrate from PostgreSQL or Tantor DB, first install the latest minor version and then perform a data offload/restore by applying pg_dumpall, or use the pg_upgrade utility.