Redundant variants and attributes imported by mistake

[ThomasU]

Dear Prestashop developers,

as my shop is too slow I am moving to a new server. Additionally I try to get rid of unused or redundant data, which might slow down my system. Doing this, I realized that my store has build up a big amount of variants, which are redundant (see attached image). This is surely a leftover of a product import which went wrong. I have e.g. more the 600 variants 'Size' in 'S'. All of them redundant, but probably all of them used by another product. 

I have two questions therefore:

1. Can this significally slow down my store?
2. And if it does, is there a simple way to consolidate these values?
 

By the way: same applies to attributes. I gues in a import operation values for 'location' were taken for a new attribute and I do have hundreds of attributes like '316' and '317' with is actually a value for a stock location (box 316 containing garments). See pic 2. Can I just delete them or will this cause troubles?

Thank you

Thomas