This trace flag (available in SQL Server 2008 R2 SP1 and later) alters the threshold calculation for auto statistics update on SQL Server instances so that larger tables do not require as many updates before statistics are updated i.e. the old 20% + 500 rows calculation does not apply for larger tables.
Personally, I would always set this as a start-up parameter on instances hosting PeopleSoft databases as in general those systems have a small number of very large tables which typically also have significant columns with a skewed data distribution.
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