Recently I optimized a huge Craft CMS project with 127 sites, a 51 GB database and over 48k frontend pages.
In the end, the DB was 30GB smaller and the frontend pages ~41% faster.
Here is the full article: https://samuelreichor.at/blogs/craft-optimize-a-large-site

Samuel ReichörOptimizing a Craft CMS Project with 127 SitesThis post documents the process of optimizing a Craft CMS project with 127 sites, a 51 GB database and over 48k frontend pages.
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