Prestashop cart slow because of a big cart response

[chattago2002]

I'm using Prestashop 1.7.8.10 and I have a "problem", inherent in all PS 1.7 versions I believe.

I have less then 150 products in my catalog but each product has combinations, for a total of about 1500 combinations.

When a user add items to cart the response is exponentially slower; on the contrary, with every product that is removed the cart response is faster (in the attached image you can see the remove operation of all items in the cart, one by one, and the response is faster and faster).

I think the problem could be that response contains a lot of details about items in the cart, including superfluous information. For each product in the cart there's the list of "main_variants" of the item, so if you have 10 products in the cart and each product has 10 variants, the response includes details for all 100 variants.

Why is this "main_variants" attribute (object) useful in the cart response? Is there a way to avoid it in the cart response? Is this a different problem otherwise?

P.S. I have a few cart rules (about 40), not so many I believe, mainly related to customer and not to products (or cart amount).

 

Thanks