We have a very critical report that runs a stored procedure on SQL 2008 R2. When the sp is executed it starts creating tempdb internal objects. I normally run a query to check these outstanding internal objects page counts and I can see the count of these objects increasing. Initially the tempdb has 100% free space in the datafiles but as this stored proc runs it fills up the 300 GB tempdb drive. The query will continue running for hours until it times out due to disk space issue and lack of space in the tempdb database. I restored the database in the test instance and ran the same report and it executes within 3-5 minutes and it doesn't fill up the tempdb. The difference between test and prod is that test is SQL 2014 and prod is SQL 2008. Also, I am updating the stats with FULL scan every second day and index fragmentation is well under control. Can any Gurus please point me in the right direction to troubleshoot this issue?