Friday, May 25, 2007

3GB PAE AWE

I once posted some information about the 3GB, AWE and PAE settings.
Here is some more detailed information about these settings. Definitely worth reading!

Tuesday, May 22, 2007

Database Snapshot vs Procedure Cache

I recently stumbled upon a KB article (KB917828) that points out some situations in which your procedure cache is cleared.

Since one of our architectures for reporting involved database snapshots I was suprised to read that your whole procedure cache is cleared when you drop a database snapshot. This may not be as dramatic as it sounds but you should closely watch the impact on your environment when the cache is cleared.

Other situations are:
  • A database has the AUTO_CLOSE database option set to ON. When no user connection references or uses the database, the background task tries to close and shut down the database automatically.
  • A database has the AUTO_CLOSE database option set to ON. Maintenance operations are performed, such as the DBCC CHECKDB operation or a backup operation. When the operations finish, the background task tries to close and shut down the database automatically.
  • You run several queries against a database that has default options. Then, the database is dropped.
  • You change the database state to OFFLINE or ONLINE.
  • You successfully rebuild the transaction log for a database.
  • You restore a database backup.