Database server overload

We are experiencing an issue with our OJS 33016 journal portal. Our database is located on an external database server, but when OJS performs the query shown at the end, the database server becomes overloaded, causing it to crash and, as a knock-on effect, causing the journal portal to crash. Is the query identified by the database server administrator normal? Please help us find a hypothesis so that we can arrive at a solution.

SELECT o . submission_id ,

MAX ( s . context_id ) AS journal_id ,

MAX ( i . date_published ) AS i_pub ,

MAX ( p . date_published ) AS s_pub ,

COUNT ( * ) AS count

FROM submissions s

JOIN publications p

ON ( p . publication_id = s . current_publication_id )

JOIN publication_settings ps

ON ( ps . publication_id = p . publication_id

AND ps . setting_name = ?

AND ps . locale = ? )

JOIN issues i

ON ( CAST ( i . issue_id AS CHAR ( ? ) ) = ps . setting_value

AND i . journal_id = s . context_id )

JOIN submission_search_objects o

ON ( s . submission_id = o . submission_id )

JOIN journals j

ON j . journal_id = s . context_id

LEFT JOIN journal_settings js

ON j . journal_id = js . journal_id

AND js . setting_name = ? NATURAL

JOIN submission_search_object_keywords o0 NATURAL

JOIN submission_search_keyword_list k0 ,

submission_search_object_keywords o1 NATURAL

JOIN submission_search_keyword_list k1 ,

submission_search_object_keywords o2 NATURAL

JOIN submission_search_keyword_list k2 ,

submission_search_object_keywords o3 NATURAL

JOIN submission_search_keyword_list k3 ,

submission_search_object_keywords o4 NATURAL

JOIN submission_search_keyword_list k4 ,

submission_search_object_keywords o5 NATURAL

JOIN submission_search_keyword_list k5 ,

submission_search_object_keywords o6 NATURAL

JOIN submission_search_keyword_list k6

WHERE ( js . setting_value <> ?

OR js . setting_value IS ? )

AND j . enabled = ?

AND s . status = ?

AND i . published = ?

AND k0 . keyword_text = ?

AND k1 . keyword_text = ?

AND o0 . object_id = o1 . object_id

AND o0 . pos + ? = o1 . pos

AND k2 . keyword_text = ?

AND o0 . object_id = o2 . object_id

AND o0 . pos + ? = o2 . pos

AND k3 . keyword_text = ?

AND o0 . object_id = o3 . object_id

AND o0 . pos + ? = o3 . pos

AND k4 . keyword_text = ?

AND o0 . object_id = o4 . object_id

AND o0 . pos + ? = o4 . pos

AND k5 . keyword_text = ?

AND o0 . object_id = o5 . object_id

AND o0 . pos + ? = o5 . pos

AND k6 . keyword_text = ?

AND o0 . object_id = o6 . object_id

AND o0 . pos + ? = o6 . pos

AND i . journal_id = ?

GROUP BY o . submission_id

ORDER BY count DESC LIMIT ?

Check if the “Recommend Similar Articles” plugin is active. If it is, disable it and see if the problem is resolved.

If it is not, check for bots (e.g., Google bot, Bing, and other lesser-known ones) indexing searches on your OJS. You can adjust the robots.txt file to indicate that they should not index */search/, if this is the case.

Thank you very much, @abadan. We made those recommendations and are monitoring the database server. I will let you know if we achieve any stability on the journal portal.