So far from the CTP release of SQL Server 2008 there has been few enhancements to the Database Mirroring, few of them I would like to list from what has been stated in BOL: Log Performance Enhancements Compression of stream data for which at least a 12.5 percent compression ratio can be achieved. Write-ahead on the incoming log stream on the mirror server. In SQL Server 2008, when receiving incoming log records, the mirror server hardens them (that is, writes them to disk) asynchronously. At the...(
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