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If there are a lot of concurrent requests to your app, it might also be prudent to tune your application server as per Deployment Best Practices#WebApplicationServerConfiguration.
Do update your database server to the latest MySQL releases. New stable database engine releases usually have performance improvments.
If you use a lot of form grids with parent and child database tables, do add indexes to your foreign key child table. This will speed up retrieval of the child form records.
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