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Do I want to store the
tempdb log files on the same drive as my user database log files, the same drive as the
tempdb data file, or on a separate drive?
It depends on how many disks you have available, how active your databases are going to be, and how much data work tempDB will see. In our environments we put tempDB on its own disk and size it out, with the log file lumped in with the user log files and have not had any issues. Of course, monitor for contention and keep an eye on everything. Here are some links for further reading: