Input on caching methods?

Make sure you understand the difference between caching the view and caching the data. Once you have the data, php generates views very quickly. You'd have to have remarkable traffic for the view generation to be your bottleneck. Caching your data that comes from a database / api can grant you significant gains though.

I'd recommend checking through the profiler what your biggest bottleneck is and then start tackling it from there. I'd guess that your database calls are what is costing the most, so start off by caching those accordingly. Eventually, if you have optimized everything else and you still need performance, you may want to look at something else for your view generation like a front end framework.

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