As I mentioned in a previous post, one of the new features for database mirroring in SQL Server 2008 is log stream compression. There's a good explanation of what this is (along with some example workloads and performance graphs) on the SQL Customer Advisory Team blog so I'm not going to duplicate all that here. Basically, the way mirroring works is by shipping all the transaction log from the principal to the mirror, and then replaying the log records on the mirror database. Network bandwidth can...(
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Read the complete post at http://www.sqlskills.com/blogs/paul/2007/10/11/SQLServer2008PerformanceBoostForDatabaseMirroring.aspx