Do I really need unordered_map?

[stereomatching]

I need to store about 0.1million int into the unordered_map and need the key(int, int) to search them
The size of the data are fixed, and I don't need to change the data so oftenly
Search is much more often than insert(more than 20 times of insert)
I try to find the answer from books and google and become more confused than before

Someone said: When the data are huge, you should use map, because it is faster than vector blablabla

Someone said: Vector could be faster than unordered_map sometimes, because the memory of vector is contiguous blablabla

I don't know which side should I trust?Could anybody help me?
thanks a lot