How to optimize your website speed by improving the backend
- The N+1 query problem slows down many apps when several queries are issued to linked fields in a database. You can use the ActiveRecord ORM tool in Rails that employs eager loading of all associated elements with a single query to help solve this problem.
- Normalize relational databases at the design stage itself and ensure effective indexing so the indexes don’t slow down your website. In some cases, denormalization is more effective though - where there are many table joins, adding an extra field to one table may be better or adding calculated values you need often to a table can help if you frequently execute complicated calculations.
- Cache carefully to speed up your site. For SQL caching in Rails, use low-level caching to store query results for a longer time. In general, prefer fragment caching of page blocks for dynamic web apps, use page caching in Rails with the actionpack-page_caching gem, but avoid it if your web has frequently updated content like news feeds. For authentication actions and error messages, use the actionpack-action_caching gem.
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