We have a certain query that now seems to result in tempdb growing until the disk runs out of space. This has started happening recently, and seems to be very similar to an issue we had about a year ago. The problem is alleviated if you supply a MAXDOP hint and ask the engine to use MAXDOP 1. It looks like theere may be a bug whereby the optimizer uses a different DOP and keeps trying to allocate more and more space for a worktable in tempdb until it runs out of space.
I had opened a case with Microsoft at the time, and they had finally acknowledged that it was a bug. Anyone know if this has been fixed yet ? I cannot find any references to this bug or itss listing as a bug or a resolution. I can provide MSFT case # upon request.