DataKeeper for Windows All Documentation - SIOS

TargetSnapshotBlocksize Registry ValueTargetSnapshotBlocksize Registry ValueDataKeeper target snapshot uses a default block size of 64KB for all entries that are written to the snapshotfile. This block size can be modified by creating a REG_DWORD value named TargetSnapshotBlocksize in theVolume registry key.The value should always be set to a multiple of the disk sector size, which is usually 512 bytes. Certainworkloads and write patterns can benefit from changing the block size. For example, a volume that is writtenin a sequential stream of data (e.g. SQL Server log files) can benefit from a larger block size. A large blocksize results in fewer reads from the target volume when consecutive blocks are written. But a volume that iswritten in a random pattern may benefit from a smaller value or the default 64KB. A smaller block size willresult in less snapshot file usage for random write requests.SQL Server NotesIf you are using DataKeeper target snapshot with SQL Server in a SteelEye Protection Suite environment, it isrecommended that you use a separate SQL Server instance to attach database(s) to the snapshot.For a clustered SQL Server environment, you must use a separate SQL Server instance to attach database(s)to the snapshot.Known IssuesMicrosoft .NET Framework 3.5 SP1 RequirementThe target snapshot feature requires Microsoft .NET Framework 3.5 SP1 to be installed - download from:http://www.microsoft.com/net.NTFS File System MessageIf an internal snapshot error occurs after target snapshot is initiated (such as the snapshot file running out ofspace or being detached by the user), snapshot will be disabled, the volume will be locked and snapshot filesDataKeeper for Windows Technical DocumentationPage 140