After upgrading to Spotlight on SQL Server Enterprise from 7.x to 8.01, there are sudden transaction log increases (GB's in a few minutes).
Running a trace reveals several DELETE TOP(500000) statements on the spotlight_perfdata and spotlight_timestamps tables in the SpotlightStatisticsRepository database.
The 500,000 is hardcoded in the SSRCleaner. Previously it was unbounded.
The change was made in v7.6 to reduce the size of the transaction logs. It is not possible to configure it.
The storage demands for SQL 2008 transaction logs are much greater than previous versions, see for example:
http://blogs.msdn.com/b/sqlserverfaq/archive/2009/08/29/a-delete-statement-in-sql-server-2000-takes-around-1-5-gb-of-transaction-log-space-where-as-in-sql-2008-it-can-take-around-3-2-gb.aspx
