While working on the one of the more content-heavy websites at my workplace (over 100k nodes consisting of galleries of photos, with some galleries having well over 2000 photos), I had noticed that while performance for logged in users (which isn't high since only site editors can log in) has mostly stabilized (there are areas where performance can improve), performance for all other site visitors was very inconsistent. Some of the galleries and gallery photos pages seemed to load fairly quickly while others took a few seconds for the page to show up.

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