pe_databases
Version information
This version is compatible with:
- Puppet Enterprise 2023.2.x, 2023.1.x, 2023.0.x, 2021.7.x, 2021.6.x, 2021.5.x, 2021.4.x, 2021.3.x, 2021.2.x, 2021.1.x, 2021.0.x, 2019.8.x
- Puppet >= 6.16.0 < 8.0.0
- , , , , ,
Tasks:
- reset_pgrepack_schema
Start using this module
Add this module to your Puppetfile:
mod 'puppetlabs-pe_databases', '2.2.0'
Learn more about managing modules with a PuppetfileDocumentation
Table of Contents
Overview
This module provides tuning, maintenance, and backups for PE PostgreSQL.
What does this module provide?
This module provides the following functionaility
- Customized settings for PE PostgreSQL
- Maintenance to keep the
pe-puppetdb
database lean and fast - Backups for all PE PostgreSQL databases, disabled by default
- The
pe-puppetdb
database is backed up every week - Other databases are backed up every night
Usage
In order to use this module, classify the node running PE PostgreSQL with the pe_databases
class.
The Primary Server and Replica run PE PostgreSQL in most instances, but there may be one or more servers with this role in an XL deployment
To classify via the PE Console, create a new node group called "PE Database Maintenance". Then pin the node(s) running pe-postgresql to that node group. It is not recommended to classify using a pre-existing node group in the PE Console.
Items you may want to configure
Backup Schedule
WARNING: The backup functionality in this module has been deprecated and will be removed in a future release. Please refer to the PE Backup and Restore documentation for details on how to backup. You should ensure the parameter
pe_databases::manage_database_backups
and any parameters from thepe_databases::backup
class are removed from classification or hiera. You should also clean up associated crontab entries.
Backups are not activated by default but can be enabled by setting the following parameter:
Hiera classification example
pe_databases::manage_database_backups:: true
You can modify the default backup schedule by provide an array of hashes that describes the databases to backup and their backup schedule. Please refer to the hieradata_examples directory of this repository for examples.
IMPORTANT NOTE: If you change the default schedule, it will stop managing the associated crontab entries, and there's not a clean way to automatically remove unmanaged crontab entries. So you should delete all pe-postgres crontab entries via
crontab -r -u pe-postgres
and let Puppet repopulate them if you change the default schedule. Otherwise, you will create duplicate backups.
Backup Retention Policy
By default, the backup script will retain two backups for each database.
When the backup script runs, it will remove the older of the two backups before starting the backup itself.
You can configure the retention policy by setting pe_databases::backup::retention_policy: <NUMBER_OF_BACKUPS_TO_RETAIN>
.
Disable Maintenance
The maintenance systemd timers will perform a pg_repack
on various pe-puppetdb
tables to keep them lean and fast.
pg_repack is a non blocking operation and should have no impact on the operations of Puppet Enterprise, however, if for some reason you experience issues you can disable the maintenance systemd timers.
You can do so by setting pe_databases::disable_maintenance: true
in your hieradata.
General PostgreSQL Recommendations
Tuning
Under normal operating conditions, there is very little tuning needed for PE PostgreSQL.
If you are using a Monolithic installation of Puppet Enterprise then the default settings are well-tuned. If you are using a dedicated node for PE PostgreSQL, then some of the settings can be tuned upwards, but likely with little difference in performance.
This module attempts to provide default settings that accommodate both a Monolithic install and a dedicated PE PostgreSQL instance.
Those defaults change based on the $all_in_one_pe
parameter.
Backups
WARNING: The backup functionality in this module has been deprecated and will be removed in a future release. Please refer to the PE Backup and Restore documentation for details on how to backup. You should ensure the parameter
pe_databases::manage_database_backups
and any parameters from thepe_databases::backup
class are removed from classification or hiera. You should also clean up associated crontab entries.
This is the documentation for Pupet Enterprise backups:
https://puppet.com/docs/pe/latest/backing_up_and_restoring_pe.html
This module provides an alternative to backup just the PE PostgreSQL databases.
It is recommended that you backup each database individually so that if you have an issue with one database you do not have to restore all databases.
Under ideal conditions you would backup all databases daily, however, backing up large databases such as pe-puppetdb
, results in excessive disk I/O so you may prefer to backup pe-puppetdb
weekly while backing up the rest of the smaller databases daily.
The choice to backup pe-puppetdb
more frequently should be based on the business needs.
This module provides a script for backing up PE PostgreSQL databases and two default cron jobs: one weekly to back up the pe-puppetdb
database, and one daily to backup every database except pe-puppetdb
.
Maintenance
This module provides systemd timers to pg_repack tables in the pe-puppetdb
database:
- facts tables are pg_repack'd Tuesdays and Saturdays at 4:30AM
- catalogs tables are pg_repack'd Sundays and Thursdays at 4:30AM
- reports table is pg_repack'd on the 10th of the month at 05:30AM on systems with PE 2019.7.0 or less
- resource_events table is pg_repack'd on the 15th of the month at 05:30AM on systems with PE 2019.3.0 or less
- other tables are pg_repack'd on the 20th of the month at 5:30AM
Note: You may be able to improve the performance (reduce time to completion) of maintenance tasks by increasing the maintenance_work_mem setting.
Please note that when using pg_repack
as part of the pe_databases module, unclean exits can leave behind the schema when otherwise it should have been cleaned up. This can result in the messages similar to the following:
INFO: repacking table "public.fact_paths"
WARNING: the table "public.fact_paths" already has a trigger called "repack_trigger"
DETAIL: The trigger was probably installed during a previous attempt to run pg_repack on the table which was interrupted and for some reason failed to clean up the temporary objects. Please drop the trigger or drop and recreate the pg_repack extension altogether to remove all the temporary objects left over.
The module now contains a task reset_pgrepack_schema
to mitigate this issue. This needs to be run against your Primary or PE-postgreSQL server to resolve this and it will drop and recreate the extension, removing the temporary objects.
PostgreSQL Settings
maintenance_work_mem
You can improve the speed of vacuuming, reindexing, and backups by increasing this setting.
Consider a table that is 1GB.
If maintenance_work_mem
is 256MB
, then to perform operations on the table a quarter of it will be read into memory, operated on, then written out to disk, and then that will repeat three more times.
If maintenance_work_mem
is 1GB
then the entire table can be read into memory, operated on, then written out to disk.
Note: that each autovacuum worker can use up to this much memory, if you do not set autovacuum_work_mem as well.
work_mem
Puppet Enterprise ships with a default work_mem
of 4MB
.
For most installations, this is all that is needed, however, at a larger scale you may need to increase to 8MB
or 16MB
.
One way to know if you need more work_mem
is to change the log_temp_files
setting to 0 which will log all temporary files created by PostgreSQL.
When you see a lot of temporary files being logged over the work_mem
threshold then it’s time to consider increasing work_mem
, however, you should first run a REINDEX
and VACUUM ANALYZE
to see if that reduces the number of temporary files being logged.
Another way to determine the need for an increase in work_mem
is to get the query plan from a slow running query (accomplished by adding EXPLAIN ANALYZE
to the beginning of the query).
Query plans that have something like Sort Method: external merge Disk
in them indicate a possible need for for more work_mem
.
This is discussed on the Tuning Your PostgreSQL Server Wiki
autovacuum_work_mem
This setting is essentially maintenance_work_mem
but for autovacuum processes only.
Usually you will set maintenance_work_mem
higher and this lower, since autovacuum_work_mem
is used by autovacuum_max_workers
number of autovacuum processes.
autovacuum_max_workers
The larger your database the more autovacuum workers you may need.
The default of 3
is reasonable for most small or medium installations of Puppet Enterprise.
When you’re tracking the size of your database tables and indexes and you notice some of them seem to keep getting larger then you might need more autovacuum workers.
If you’ve installed PE PostgreSQL on its own node, then we recommend CPU / 2
as a default for this setting (with a maximum of 8).
For a Monolithic installation, increasing this setting means you likely need to compensate by reducing other settings that may cause your CPU to be over-subscribed during a peak.
Those settings would be PuppetDB Command Processing Threads and Puppet Server JRuby Instances.
checkpoint_segments and checkpoint_completion_target
We suggest a middle ground of 128
for checkpoint_segments
and .9
for checkpoint_completion_target
.
As mentioned in the PostgreSQL Wiki, the larger value you use for checkpoint_segments
affords you better performance but you sacrifice in potential recovery time.
If you see messages like “LOG: checkpoints are occurring too frequently (xx seconds apart)” then you definitely want to increase your checkpoint_segments
.
How to Report an issue or contribute to the module
If you are a PE user and need support using this module or are encountering issues, our Support team would be happy to help you resolve your issue and help reproduce any bugs. Just raise a ticket on the support portal. If you have a reproducible bug or are a community user you can raise it directly on the Github issues page of the module puppetlabs/puppetlabs-pe_databases. We also welcome PR contributions to improve the module. Please see further details about contributing here
Reference
Table of Contents
Classes
pe_databases
pe_databases::backup
pe_databases::pg_repack
pe_databases::postgresql_settings
pe_databases::postgresql_settings::table_settings
Defined types
pe_databases::collect
: Create systemd units for repacking a given database typepe_databases::set_puppetdb_table_autovacuum_cost_delay_zero
pe_databases::set_table_attribute
Functions
Tasks
reset_pgrepack_schema
: This task will remove and recreate the pg_repack extension
Classes
pe_databases
The pe_databases class.
Parameters
The following parameters are available in the pe_databases
class:
manage_database_backups
manage_database_maintenance
disable_maintenance
manage_postgresql_settings
manage_table_settings
install_dir
scripts_dir
manage_database_backups
Data type: Variant[Boolean,Undef]
Default value: undef
manage_database_maintenance
Data type: Boolean
Default value: true
disable_maintenance
Data type: Boolean
Default value: lookup('pe_databases::disable_maintenance', {'default_value' => false})
manage_postgresql_settings
Data type: Boolean
Default value: true
manage_table_settings
Data type: Boolean
Default value: false
install_dir
Data type: String
Default value: '/opt/puppetlabs/pe_databases'
scripts_dir
Data type: String
Default value: "${install_dir}/scripts"
pe_databases::backup
The pe_databases::backup class.
Parameters
The following parameters are available in the pe_databases::backup
class:
databases_and_backup_schedule
psql_version
backup_directory
backup_script_path
daily_databases_path
backup_logging_directory
retention_policy
disable_maintenance
databases_and_backup_schedule
Data type: Array[Hash]
Default value: [ { 'databases' => pe_databases::version_based_databases(), 'schedule' => { 'minute' => '30', 'hour' => '22', }, }, { 'databases' => ['pe-puppetdb'], 'schedule' => { 'minute' => '0', 'hour' => '2', 'weekday' => '7', }, } ]
psql_version
Data type: String
Default value: $pe_databases::psql_version
backup_directory
Data type: String
Default value: "/opt/puppetlabs/server/data/postgresql/${psql_version}/backups"
backup_script_path
Data type: String
Default value: "${pe_databases::scripts_dir}/puppet_enterprise_database_backup.sh"
daily_databases_path
Data type: String
Default value: "${pe_databases::install_dir}/default_daily_databases.txt"
backup_logging_directory
Data type: String
Default value: '/var/log/puppetlabs/pe_databases_backup'
retention_policy
Data type: Integer
Default value: 2
disable_maintenance
Data type: Boolean
Default value: true
pe_databases::pg_repack
The pe_databases::pg_repack class.
Parameters
The following parameters are available in the pe_databases::pg_repack
class:
disable_maintenance
Data type: Boolean
Default value: false
jobs
Data type: Integer
Default value: /
pe_databases::postgresql_settings
The pe_databases::postgresql_settings class.
Parameters
The following parameters are available in the pe_databases::postgresql_settings
class:
autovacuum_vacuum_scale_factor
autovacuum_analyze_scale_factor
autovacuum_max_workers
log_autovacuum_min_duration
log_temp_files
work_mem
max_connections
arbitrary_postgresql_conf_settings
checkpoint_completion_target
checkpoint_segments
manage_postgresql_service
all_in_one_pe_install
manage_reports_autovacuum_cost_delay
factsets_autovacuum_vacuum_scale_factor
reports_autovacuum_vacuum_scale_factor
maintenance_work_mem
autovacuum_work_mem
psql_version
autovacuum_vacuum_scale_factor
Data type: Float[0,1]
Default value: 0.08
autovacuum_analyze_scale_factor
Data type: Float[0,1]
Default value: 0.04
autovacuum_max_workers
Data type: Integer
Default value: max(3, min(8, $facts['processors']['count'] / 3))
log_autovacuum_min_duration
Data type: Integer
Default value: -
log_temp_files
Data type: Integer
Default value: -
work_mem
Data type: String
Default value: '8MB'
max_connections
Data type: Integer
Default value: 1000
arbitrary_postgresql_conf_settings
Data type: Hash
Default value: {}
checkpoint_completion_target
Data type: Float[0,1]
Default value: 0.9
checkpoint_segments
Data type: Integer
Default value: 128
manage_postgresql_service
Data type: Boolean
Default value: true
all_in_one_pe_install
Data type: Boolean
Default value: true
manage_reports_autovacuum_cost_delay
Data type: Boolean
Default value: true
factsets_autovacuum_vacuum_scale_factor
Data type: Optional[Float[0,1]]
Default value: 0.80
reports_autovacuum_vacuum_scale_factor
Data type: Optional[Float[0,1]]
Default value: 0.01
maintenance_work_mem
Data type: String
Default value: $all_in_one_pe_install
autovacuum_work_mem
Data type: String
Default value: $all_in_one_pe_install
psql_version
Data type: String
Default value: $pe_databases::psql_version
pe_databases::postgresql_settings::table_settings
The pe_databases::postgresql_settings::table_settings class.
Parameters
The following parameters are available in the pe_databases::postgresql_settings::table_settings
class:
manage_reports_autovacuum_cost_delay
factsets_autovacuum_vacuum_scale_factor
reports_autovacuum_vacuum_scale_factor
catalogs_autovacuum_vacuum_scale_factor
certnames_autovacuum_vacuum_scale_factor
manage_reports_autovacuum_cost_delay
Data type: Boolean
Default value: lookup('pe_databases::postgresql_settings::manage_reports_autovacuum_cost_delay', {'default_value' => true})
factsets_autovacuum_vacuum_scale_factor
Data type: Optional[Float[0,1]]
Default value: lookup('pe_databases::postgresql_settings::factsets_autovacuum_vacuum_scale_factor', {'default_value' => 0.80})
reports_autovacuum_vacuum_scale_factor
Data type: Optional[Float[0,1]]
Default value: lookup('pe_databases::postgresql_settings::reports_autovacuum_vacuum_scale_factor', {'default_value' => 0.01})
catalogs_autovacuum_vacuum_scale_factor
Data type: Optional[Float[0,1]]
Default value: 0.75
certnames_autovacuum_vacuum_scale_factor
Data type: Optional[Float[0,1]]
Default value: 0.75
Defined types
pe_databases::collect
Create systemd units for repacking a given database type
Parameters
The following parameters are available in the pe_databases::collect
defined type:
database_type
Data type: String
Default value: $title
command
Data type: String
Default value: undef
disable_maintenance
Data type: Boolean
Default value: false
on_cal
Data type: String
Default value: undef
pe_databases::set_puppetdb_table_autovacuum_cost_delay_zero
The pe_databases::set_puppetdb_table_autovacuum_cost_delay_zero class.
Parameters
The following parameters are available in the pe_databases::set_puppetdb_table_autovacuum_cost_delay_zero
defined type:
table_name
Data type: String
Default value: $title
pe_databases::set_table_attribute
The pe_databases::set_table_attribute class.
Parameters
The following parameters are available in the pe_databases::set_table_attribute
defined type:
db
Data type: String
table_name
Data type: String
table_attribute
Data type: String
table_attribute_value
Data type: String
Functions
pe_databases::version_based_databases
Type: Puppet Language
The pe_databases::version_based_databases function.
pe_databases::version_based_databases()
The pe_databases::version_based_databases function.
Returns: Array[String]
Tasks
reset_pgrepack_schema
This task will remove and recreate the pg_repack extension
Supports noop? false
What are tasks?
Modules can contain tasks that take action outside of a desired state managed by Puppet. It’s perfect for troubleshooting or deploying one-off changes, distributing scripts to run across your infrastructure, or automating changes that need to happen in a particular order as part of an application deployment.
Tasks in this module release
reset_pgrepack_schema
This task will remove and recreate the pg_repack extension
Change log
All notable changes to this project will be documented in this file. The format is based on Keep a Changelog and this project adheres to Semantic Versioning.
v2.2.0 (2021-10-06)
Added
- (SUP-2677) Deprecate backup functionality #96 (elainemccloskey)
Fixed
- (SUP-2571) Purge legacy cron jobs if present #97 (gavindidrichsen)
- (SUP-2557) Ensure backup class is not included by default #95 (m0dular)
v2.1.1 (2021-09-30)
Fixed
v2.1.0 (2021-07-13)
Added
v2.0.0 (2021-07-02)
Changed
- Remove Puppet 5 support and EOL PE versions #76 (MartyEwings)
- SUP-2404 Migrate from cron to systemd timers #65 (m0dular)
Added
- Addition of SLES 12 Test Platform #77 (MartyEwings)
Fixed
- Fix path in backup.pp and reset pgrepack schema task #74 (carabasdaniel)
- Fix scope of disable_maintenance param #73 (m0dular)
v1.2.0 (2021-06-02)
Added
- Adding catalog_inputs to the pg_repack scheme for PE 2019.8.0+ #54 (coreymbe)
- (SUP-2372) add pg_repack schema reset task #53 (pgrant87)
- (SUP-2374) Remove external module deps #51 (MartyEwings)
- (sup-2095) Remove cron_core from dependencies #49 (jarretlavallee)
v1.1.0 (2020-08-07)
Added
Fixed
- (GH-30) Update repack logging to separate files #43 (jarretlavallee)
1.0.1 (2020-03-25)
1.0.0 (2020-03-20)
Added
Fixed
0.15.0 (2019-02-06)
Added
- Add pg_repack as default maintenance strategy #25 (npwalker)
- Allow not managing table settings #21 (reidmv)
Fixed
- PE Database is a reserved node group name in 2019.0 #24 (MartyEwings)
- Set permissions on /opt/puppetlabs/pe_databases and /opt/puppetlabs/pe_databases/scripts #18 (mmarod)
0.14.2 (2018-11-01)
0.14.1 (2018-06-25)
0.14.0 (2018-05-23)
Added
- Update for compatibility with 2018.1.0 #17 (npwalker)
- Add autovacuum settings for certnames and catalogs #14 (npwalker)
0.13.0 (2017-12-01)
0.12.1 (2017-11-02)
Added
- Add analyze when performing VACUUM FULL #13 (npwalker)
- Make cronjobs to vacuum full PuppetDB tables #12 (npwalker)
0.12.0 (2017-10-18)
0.11.2 (2017-09-19)
0.11.1 (2017-09-19)
0.11.0 (2017-09-19)
Fixed
0.10.1 (2017-06-19)
0.10.0 (2016-12-08)
0.9.0 (2016-12-05)
0.8.1 (2016-10-17)
0.8.0 (2016-10-17)
Added
* This Changelog was automatically generated by github_changelog_generator
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We also recommend that a file or class name and description of purpose be included on the same "printed page" as the copyright notice for easier identification within third-party archives. Copyright 2016 Nick Walker Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.