How long must I stay in Canada to keep my permanent resident status? https://www.cic.gc.ca/english/helpcentre/answer.asp?qnum=727&top=10
To keep your permanent resident status, you must have been in Canada for at least 730 days during the last five years. These 730 days don’t need to be continuous. Some of your time abroad may count towards the 730 days.
a Canadian business or organization, or
the Canadian federal, provincial or territorial government
You travel with a spouse or common-law partner
Your spouse or common-law partner needs to be:
a Canadian citizen, or
a permanent resident working outside Canada, full-time for:
a Canadian business, or
the Canadian federal, provincial or territorial government