Aggregates + Query Performance

I build an aggreate on a cube , it has 2 queries and I want to improve the performance for these queries. So I created the aggregates by 'Propose By query'.

So I got Min and Max on the screen , then I saved and activated the aggregate. Ran the query in , when I look in the aggregates screen now after activating again , I see , under records 127252 and under records summarized 1.

I went to RSRT and typed my query name and clicked on Performance Info and it says RSRV Check is necessary.

Well,

Question 1. What is this RSRV issue?

Question 2. How do I compare the performance of the query before and after aggregates.

Thanks