OJS 3.0 suddenly slow. Hosting provider blaming OJS

[marc]

Did you confirm all your DBs and tables are with the same engine?
When they are mixed, performance can drop dramatically.

The recomendation is innoDB:

Mariadb/mysql hangs when you search for user to add to journal

Well… I’m not a DB expert but those nested left joins look quite stressing for any server. But if you like you can try with a different approach: You can notice performance issues when you have mixed engines (move all MyISAM to InnoDB) or mixed charsets. A mysqldump, edit your dump and recreate the DB is usually the best way to do those engine and charset changes… but feel free to try with ALTER table if you like (of course, remember to make a DB backup first ). Cheers, m…

Cheers,
m.