Hello,
While I am using survey, my session close after less 30 minutes of inactivity, so I change the value of : session.gc_maxlifetime in the cpanel from 1440 to 3600, and still have the same issue, so :
1- Is this the right variable to change
2- Should I restart any service, or the hoste server?
Thanks

Since this is a server issue, it seems to me that this is a question for your hosting provider.