After you get your PR and land in Canada, you need 1095 days (3 years) in Canada before you can apply for citizenship. If you take vacations outside Canada, those days will not count towards the 1095 so you will have to wait longer. The 1095 days need to be within a 4 year period.
Processing citizenship takes on average another year.
Do you mean that it takes a year only for immigration to give you a decision regarding your application for Canadian citizenship? If so, that sure is a positive thing!