SQLs taking too long and using 100% of processors

Oberdan · March 2, 2026, 5:40pm

Hello All,

Some days ago I ran a test upgrade of our OJS 3.3 to 3.5. While able to solve most problems, there is still one pending that I could not figure out. There are some queries that are taking forever to run and using 100% of the server four cores.

I’ve already blocked bots, ajusted the memory for MariaDB, optimized indexes, but nothing worked yet. Here are the query that causes this and the outputs of show processlist:

https://ojs-teste.biblioteca.unesp.br/temp/query_example.sql

https://ojs-teste.biblioteca.unesp.br/temp/show_processlist.txt

https://ojs-teste.biblioteca.unesp.br/temp/show_full_processlist.txt

Is it possible that there are missing indexes? Should I try using the SOLR plugin mentioned on previous threads because MariaDB becomes slow with large databases? Any help would be greatly appreciated.

Best regards,

Oberdan

asmecher · March 2, 2026, 7:52pm

Hi @Oberdan,

There’s an issue filed here with a patch that may well resolve what you’re reporting:

github.com/pkp/pkp-lib

Improve submission list performance

opened 05:52PM - 03 Feb 26 UTC

closed 12:42AM - 21 Feb 26 UTC

asmecher

### Valid Title - [x] I have updated the title to accurately reflect the bug de…scription ### Description The submission lists do not perform well with large collections. See: - https://forum.pkp.sfu.ca/t/editor-dashboard-loading-time-in-ojs-3-5-0-3/97775 - https://forum.pkp.sfu.ca/t/performance-issues-after-upgrading-to-ojs-3-5-0-0/96133 [Some work was included in 3.5.0-2](https://github.com/pkp/pkp-lib/issues/11682), but more improvements need to be made before 3.5.0-x is ready for the LTS stamp. ### Steps to Reproduce (see forum threads) ### Expected Result (see forum threads) ### Actual Result (see forum threads) ### Environment Details _No response_ ### Application Version OJS/OMP/OPS 3.5.0-0 to 3.5.0-3 ### Logs _No response_ ### Additional Information _No response_ ### PRs #### Stable-3.5.0 ~~https://github.com/pkp/pkp-lib/pull/12316 by @mariuszsienkiewicz~~ ~~[pkp-lib](https://github.com/pkp/pkp-lib) --> https://github.com/pkp/pkp-lib/pull/12362~~ ~~[ojs](https://github.com/pkp/ojs) --> https://github.com/pkp/ojs/pull/5354 [TEST ONLY]~~ #### main [pkp-lib](https://github.com/pkp/pkp-lib) --> https://github.com/pkp/pkp-lib/pull/12370 [ojs](https://github.com/pkp/ojs) --> https://github.com/pkp/ojs/pull/5359 [TEST ONLY]

This fix will be included in OJS/OMP/OPS 3.5.0-4.

Regards,
Alec Smecher
Public Knowledge Project Team

Oberdan · March 3, 2026, 4:21pm

Hello @asmecher ,

Applied the change described here:

And it didn’t seem to make much of a difference… But maybe I’m doing it wrong…

Regards,

Oberdan

Oberdan · March 4, 2026, 5:56pm

Hello @asmecher ,

Looking again at my error_log, I’ve found a bunch of Recommended by Author and Recommended by Similarity errors:

[Tue Mar 03 13:13:31.150461 2026] [php:notice] [pid 5611] [client 143.44.165.240:38646] Plugin APP\\plugins\\generic\\recommendBySimilarity\\RecommendBySimilarityPlugin failed to handle the hook Templates::Article::Footer::PageFooter
PDOException: SQLSTATE[HY000] [2002] No such file or directory in /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php:66
Stack trace:
#0 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(66): PDO->__construct()
#1 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(85): Illuminate\\Database\\Connectors\\Connector->createPdoConnection()
#2 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(48): Illuminate\\Database\\Connectors\\Connector->tryAgainIfCausedByLostConnection()
#3 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/MySqlConnector.php(24): Illuminate\\Database\\Connectors\\Connector->createConnection()
#4 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/ConnectionFactory.php(185): Illuminate\\Database\\Connectors\\MySqlConnector->connect()
#5 [internal function]: Illuminate\\Database\\Connectors\\ConnectionFactory->Illuminate\\Database\\Connectors\\{closure}()
#6 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(1231): call_user_func()
#7 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(1267): Illuminate\\Database\\Connection->getPdo()
#8 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(512): Illuminate\\Database\\Connection->getReadPdo()
#9 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(407): Illuminate\\Database\\Connection->getPdoForSelect()
#10 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(812): Illuminate\\Database\\Connection->Illuminate\\Database\\{closure}()
#11 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(979): Illuminate\\Database\\Connection->runQueryCallback()
#12 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(958): Illuminate\\Database\\Connection->tryAgainIfCausedByLostConnection()
#13 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(781): Illuminate\\Database\\Connection->handleQueryException()
#14 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(398): Illuminate\\Database\\Connection->run()
#15 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3106): Illuminate\\Database\\Connection->select()
#16 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3091): Illuminate\\Database\\Query\\Builder->runSelect()
#17 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3676): Illuminate\\Database\\Query\\Builder->Illuminate\\Database\\Query\\{closure}()
#18 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3090): Illuminate\\Database\\Query\\Builder->onceWithColumns()
#19 /home/ojs/rc-3.5.0-3/lib/pkp/classes/submission/DAO.php(120): Illuminate\\Database\\Query\\Builder->get()
#20 [internal function]: PKP\\submission\\DAO->PKP\\submission\\{closure}()
#21 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Collections/LazyCollection.php(1818): iterator_count()
#22 /home/ojs/rc-3.5.0-3/plugins/generic/recommendBySimilarity/RecommendBySimilarityPlugin.php(115): Illuminate\\Support\\LazyCollection->count()
#23 /home/ojs/rc-3.5.0-3/plugins/generic/recommendBySimilarity/RecommendBySimilarityPlugin.php(47): APP\\plugins\\generic\\recommendBySimilarity\\RecommendBySimilarityPlugin->buildTemplate()
#24 [internal function]: APP\\plugins\\generic\\recommendBySimilarity\\RecommendBySimilarityPlugin->APP\\plugins\\generic\\recommendBySimilarity\\{closure}()
#25 /home/ojs/rc-3.5.0-3/lib/pkp/classes/plugins/Hook.php(164): call_user_func_array()
#26 /home/ojs/rc-3.5.0-3/lib/pkp/classes/plugins/Hook.php(132): PKP\\plugins\\Hook::run()
#27 /home/ojs/rc-3.5.0-3/lib/pkp/classes/template/PKPTemplateManager.php(1843): PKP\\plugins\\Hook::call()
#28 /home/ojs/rc-3.5.0-3/cache/t_compile/42362804174f266c598cdb32c3208fc745b92101^1c372c95cd85572e0fbc9a53d0323a0b229cfc78_0.app.frontendpagesarticle.tpl.php(43): PKP\\template\\PKPTemplateManager->smartyCallHook()
#29 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_resource_base.php(123): content_698f07d4bfd5b2_49284654()
#30 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_compiled.php(114): Smarty_Template_Resource_Base->getRenderedTemplateCode()
#31 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_template.php(217): Smarty_Template_Compiled->render()
#32 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_templatebase.php(238): Smarty_Internal_Template->render()
#33 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_templatebase.php(134): Smarty_Internal_TemplateBase->_execute()
#34 /home/ojs/rc-3.5.0-3/lib/pkp/classes/template/PKPTemplateManager.php(1515): Smarty_Internal_TemplateBase->display()
#35 /home/ojs/rc-3.5.0-3/pages/article/ArticleHandler.php(365): PKP\\template\\PKPTemplateManager->display()
#36 [internal function]: APP\\pages\\article\\ArticleHandler->view()\n#37 /home/ojs/rc-3.5.0-3/lib/pkp/classes/core/PKPRouter.php(327): call_user_func()
#38 /home/ojs/rc-3.5.0-3/lib/pkp/classes/core/PKPPageRouter.php(249): PKP\\core\\PKPRouter->_authorizeInitializeAndCallRequest()
#39 /home/ojs/rc-3.5.0-3/lib/pkp/classes/core/Dispatcher.php(157): PKP\\core\\PKPPageRouter->route()
#40 /home/ojs/rc-3.5.0-3/lib/pkp/classes/core/PKPApplication.php(429): PKP\\core\\Dispatcher->dispatch()
#41 /home/ojs/rc-3.5.0-3/index.php(21): PKP\\core\\PKPApplication->execute()
#42 {main}\n\nNext Illuminate\\Database\\QueryException: SQLSTATE[HY000] [2002] No such file or directory 
(Connection: mysql, SQL: select `s`.* from `submissions` as `s` left join `publications` as `po` on `s`.`current_publication_id` = `po`.`publication_id` where `s`.`context_id` in (3) and `s`.`status` in (3) and (exists (select * from `submission_search_objects` as `sso` inner join `submission_search_object_keywords` as `ssok` on `sso`.`object_id` = `ssok`.`object_id` inner join `submission_search_keyword_list` as `sskl` on `sskl`.`keyword_id` = `ssok`.`keyword_id` where `sskl`.`keyword_text` = LOWER(parque) and `s`.`submission_id` = `sso`.`submission_id`) or `s`.`submission_id` in (select `p`.`submission_id` from `publications` as `p` inner join `publication_settings` as `ps` on `p`.`publication_id` = `ps`.`publication_id` where `ps`.`setting_name` = title and LOWER(ps.setting_value) LIKE CONCAT('%', LOWER(parque), '%')) or `s`.`submission_id` in (select `p`.`submission_id` from `publications` as `p` inner join `authors` as `au` on `au`.`publication_id` = `p`.`publication_id` inner join `author_settings` as `aus` on `aus`.`author_id` = `au`.`author_id` where `aus`.`setting_name` in (givenName, familyName, orcid) and LOWER(aus.setting_value) LIKE CONCAT('%', LOWER(parque), '%')) or exists (select * from `submission_search_objects` as `sso` inner join `submission_search_object_keywords` as `ssok` on `sso`.`object_id` = `ssok`.`object_id` inner join `submission_search_keyword_list` as `sskl` on `sskl`.`keyword_id` = `ssok`.`keyword_id` where `sskl`.`keyword_text` = LOWER(nacional) and `s`.`submission_id` = `sso`.`submission_id`) or `s`.`submission_id` in (select `p`.`submission_id` from `publications` as `p` inner join `publication_settings` as

and

[Tue Mar 03 13:13:31.151081 2026] [php:notice] [pid 5611] [client 143.44.165.240:38646] Plugin APP\\plugins\\generic\\recommendByAuthor\\RecommendByAuthorPlugin failed to handle the hook Templates::Article::Footer::PageFooter
PDOException: SQLSTATE[HY000] [2002] No such file or directory in /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php:66
Stack trace:
#0 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(66): PDO->__construct()
#1 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(85): Illuminate\\Database\\Connectors\\Connector->createPdoConnection()
#2 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/Connector.php(48): Illuminate\\Database\\Connectors\\Connector->tryAgainIfCausedByLostConnection()
#3 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/MySqlConnector.php(24): Illuminate\\Database\\Connectors\\Connector->createConnection()
#4 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connectors/ConnectionFactory.php(185): Illuminate\\Database\\Connectors\\MySqlConnector->connect()
#5 [internal function]: Illuminate\\Database\\Connectors\\ConnectionFactory->Illuminate\\Database\\Connectors\\{closure}()
#6 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(1231): call_user_func()
#7 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(1267): Illuminate\\Database\\Connection->getPdo()
#8 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(512): Illuminate\\Database\\Connection->getReadPdo()
#9 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(407): Illuminate\\Database\\Connection->getPdoForSelect()
#10 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(812): Illuminate\\Database\\Connection->Illuminate\\Database\\{closure}()
#11 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(979): Illuminate\\Database\\Connection->runQueryCallback()
#12 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(958): Illuminate\\Database\\Connection->tryAgainIfCausedByLostConnection()
#13 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(781): Illuminate\\Database\\Connection->handleQueryException()
#14 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(398): Illuminate\\Database\\Connection->run()
#15 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3106): Illuminate\\Database\\Connection->select()
#16 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3091): Illuminate\\Database\\Query\\Builder->runSelect()
#17 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3676): Illuminate\\Database\\Query\\Builder->Illuminate\\Database\\Query\\{closure}()
#18 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3090): Illuminate\\Database\\Query\\Builder->onceWithColumns()
#19 /home/ojs/rc-3.5.0-3/lib/pkp/classes/author/DAO.php(142): Illuminate\\Database\\Query\\Builder->get()
#20 /home/ojs/rc-3.5.0-3/plugins/generic/recommendByAuthor/RecommendByAuthorPlugin.php(99): PKP\\author\\DAO->PKP\\author\\{closure}()
#21 [internal function]: APP\\plugins\\generic\\recommendByAuthor\\RecommendByAuthorPlugin->callbackTemplateArticlePageFooter()
#22 /home/ojs/rc-3.5.0-3/lib/pkp/classes/plugins/Hook.php(164): call_user_func_array()
#23 /home/ojs/rc-3.5.0-3/lib/pkp/classes/plugins/Hook.php(132): PKP\\plugins\\Hook::run()
#24 /home/ojs/rc-3.5.0-3/lib/pkp/classes/template/PKPTemplateManager.php(1843): PKP\\plugins\\Hook::call()
#25 /home/ojs/rc-3.5.0-3/cache/t_compile/42362804174f266c598cdb32c3208fc745b92101^1c372c95cd85572e0fbc9a53d0323a0b229cfc78_0.app.frontendpagesarticle.tpl.php(43): PKP\\template\\PKPTemplateManager->smartyCallHook()
#26 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_resource_base.php(123): content_698f07d4bfd5b2_49284654()
#27 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_template_compiled.php(114): Smarty_Template_Resource_Base->getRenderedTemplateCode()
#28 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_template.php(217): Smarty_Template_Compiled->render()
#29 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_templatebase.php(238): Smarty_Internal_Template->render()
#30 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/smarty/smarty/libs/sysplugins/smarty_internal_templatebase.php(134): Smarty_Internal_TemplateBase->_execute()
#31 /home/ojs/rc-3.5.0-3/lib/pkp/classes/template/PKPTemplateManager.php(1515): Smarty_Internal_TemplateBase->display()
#32 /home/ojs/rc-3.5.0-3/pages/article/ArticleHandler.php(365): PKP\\template\\PKPTemplateManager->display()
#33 [internal function]: APP\\pages\\article\\ArticleHandler->view()
#34 /home/ojs/rc-3.5.0-3/lib/pkp/classes/core/PKPRouter.php(327): call_user_func()
#35 /home/ojs/rc-3.5.0-3/lib/pkp/classes/core/PKPPageRouter.php(249): PKP\\core\\PKPRouter->_authorizeInitializeAndCallRequest()
#36 /home/ojs/rc-3.5.0-3/lib/pkp/classes/core/Dispatcher.php(157): PKP\\core\\PKPPageRouter->route()
#37 /home/ojs/rc-3.5.0-3/lib/pkp/classes/core/PKPApplication.php(429): PKP\\core\\Dispatcher->dispatch()
#38 /home/ojs/rc-3.5.0-3/index.php(21): PKP\\core\\PKPApplication->execute()
#39 {main}\n\nNext Illuminate\\Database\\QueryException: SQLSTATE[HY000] [2002] No such file or directory 
(Connection: mysql, SQL: select `a`.*, `s`.`locale` as `submission_locale` from `authors` as `a` inner join `publications` as `p` on `a`.`publication_id` = `p`.`publication_id` inner join `submissions` as `s` on `p`.`submission_id` = `s`.`submission_id` where `s`.`context_id` in (3) and `a`.`author_id` in (select `author_id` from `author_settings` where `setting_name` = familyName and `setting_value` = Cavalcanti) and `a`.`author_id` in (select `author_id` from `author_settings` where `setting_name` = givenName and `setting_value` = Agostinho Paula Brito) order by `a`.`seq` asc) in /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php:825\nStack trace:\n#0 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(979): Illuminate\\Database\\Connection->runQueryCallback()\n#1 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(958): Illuminate\\Database\\Connection->tryAgainIfCausedByLostConnection()\n#2 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(781): Illuminate\\Database\\Connection->handleQueryException()\n#3 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(398): Illuminate\\Database\\Connection->run()\n#4 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3106): Illuminate\\Database\\Connection->select()\n#5 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3091): Illuminate\\Database\\Query\\Builder->runSelect()\n#6 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3676): Illuminate\\Database\\Query\\Builder->Illuminate\\Database\\Query\\{closure}()\n#7 /home/ojs/rc-3.5.0-3/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Query/Builder.php(3090): Illuminate\\Database\\Query\\Builder->onceWithColumns()\n#8 /home/ojs/rc-3.5.0-3/lib/pkp/classes/author/DAO.php(142): Illuminate\\Database\\Query\\Builder->ge

To my knowledge we had disabled those plugins, but it seems that some old journals still have them enabled. Either that or there are some inconsistency in our DB regarding the plugin configuration:

Looking at versions:

MariaDB [ojs_rc_3503]> select * from versions where product like 'recommend%';
+------------+-------+-------+----------+-------+---------------------+---------+-----------------+-----------------------+-----------------------------+-----------+----------+
| version_id | major | minor | revision | build | date_installed      | current | product_type    | product               | product_class_name          | lazy_load | sitewide |
+------------+-------+-------+----------+-------+---------------------+---------+-----------------+-----------------------+-----------------------------+-----------+----------+
|         25 |     1 |     0 |        0 |     0 | 2019-05-03 08:38:11 |       0 | plugins.generic | recommendByAuthor     | RecommendByAuthorPlugin     |         1 |        1 |
|        144 |     1 |     0 |        0 |     0 | 2023-08-25 11:51:19 |       1 | plugins.generic | recommendBySimilarity | RecommendBySimilarityPlugin |         1 |        1 |
|        158 |     1 |     0 |        0 |     1 | 2026-02-02 11:47:00 |       1 | plugins.generic | recommendByAuthor     | RecommendByAuthorPlugin     |         1 |        1 |
+------------+-------+-------+----------+-------+---------------------+---------+-----------------+-----------------------+-----------------------------+-----------+----------+
3 rows in set (0.003 sec)

Looking at plugin_settings:

MariaDB [ojs_rc_3503]> select * from plugin_settings where plugin_name like 'recommend%';
+-------------------+-----------------------------+------------+--------------+---------------+--------------+
| plugin_setting_id | plugin_name                 | context_id | setting_name | setting_value | setting_type |
+-------------------+-----------------------------+------------+--------------+---------------+--------------+
|               785 | recommendbyauthorplugin     |          2 | enabled      | 1             | bool         |
|               786 | recommendbyauthorplugin     |          3 | enabled      | 1             | bool         |
|               787 | recommendbyauthorplugin     |          9 | enabled      | 1             | bool         |
|               788 | recommendbyauthorplugin     |         12 | enabled      | 1             | bool         |
|               789 | recommendbyauthorplugin     |         22 | enabled      | 1             | bool         |
|               790 | recommendbysimilarityplugin |          3 | enabled      | 1             | bool         |
|               791 | recommendbysimilarityplugin |         10 | enabled      | 1             | bool         |
|               792 | recommendbysimilarityplugin |         12 | enabled      | 1             | bool         |
|               793 | recommendbysimilarityplugin |         22 | enabled      | 1             | bool         |
+-------------------+-----------------------------+------------+--------------+---------------+--------------+
9 rows in set (0.011 sec)

There are some topics in the forum discussing how recommendByAuthor and recommendBySimilarity can slow down things.

I’ve cleaned the template cache to see if the smarty errors will stop, but I’m also thinking about disabling recommendBySimilarity and recommendByAuthor completely, or even removing them. If I remove them, will this remove the references in versions and plugin_settings too?

Regards,

Oberdan