HP Data Protector A.06.11 Integration Manual page 59

3. Adjust block sizes for local backup devices.
• Enable/disable Fast direct mode.
Use this option only if the highest performance is required. Due to specific
device settings, these device definitions should not be shared with
conventional (filesystem) backups. Therefore, using this option in general is
not recommended.
Disable Fast direct mode (as well as special local device settings) if backup
performance is not very critical and/or other data is backed up to devices
connected to SQL Server.
NOTE:
Fast direct mode is ignored for remote devices.
• Set the block size (if Fast direct mode is enabled).
Adjusted block sizes are calculated as follows:
block size (kB) = 64*N + 4 (N=1,...,64)
block size (kB) = 68, 132, ..., 4100 kB
All selected devices must have the same block size.
You can gain some performance improvement by specifying a block size
larger than 68 KB (recommended). You can also increase the block size step
by step and compare the performance achieved for each step.
You can adjust block size during the initial device definition for local devices
by checking the attached check box and selecting the block size. See
15 on page 60.
You can modify block size later; however, you must first calculate it using
the formula above and then insert the value as shown in
16 on page 61.
• Modify the registry.
To use block size larger than 56 KB, some SCSI interface cards require you
to adjust related values in the registry of the system where the device is
connected. See the online Help index: "changing block size" for instructions.
Integration guide for Microsoft applications
Figure
Figure
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