Should BLOCK_HTML invalidate EVERY time we save a product?

Question

My client raised this question today and I wanted to give a concise answer, as I understand it , the cache is only invalidated on the item that was updated?

Can anyone elaborate. This is EE 13.0.2

Answer 1

The cache is flagged as invalid but not refreshed as a performance decision (flag rather than auto-refresh), if I remember correctly. There was some discussion about this when the behavior was introduced, but it was stated as "by design" by Magento, Inc. (whether good or bad design is left to the viewer!).

As a developer though it's possible to observe product save action events and refresh the cache entry directly.

Answer 2

Maybe this helps: when creating a cache tag, make it upper case, because Magento creates a tag as you give it, but when it deletes the cache, or refreshes it, it looks for the tag in upper-case.