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The Tempdb Summary tab includes charts charts that display capacity usage and recent trend information for your tempdb database.
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Version Store Cleanup Rate
The tempdb database version store collects data rows necessary to support snapshot isolation. This chart helps you see the current cleanup rate to avoid filling up tempdb.
Tempdb Contention
The Tempdb Contention chart displays latch wait time (in milliseconds) for the allocation pages of tempdb. The three tracked allocation page types are:
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Latch contention of this sort is usually an indication that you should create more tempdb data files. In some situations, using Trace Flag 1118 may also alleviate tempdb contention.