Instruction manual

Blackmagic Software
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Blackmagic Disk Speed Test
If you want to check your disk array speed, Blackmagic Disk Speed Test can be run to check the array speed,
and to provide the results in video frame rates. This makes it much easier to understand how various disk
arrays will handle video capture and playback at various video resolutions and frame rates.
Disk Speed Test provides more accurate results for large disk arrays, as often the manufacturer provided
speed results only check small data blocks; so you only get an indication of the cache speed of the disk and
not the sustained data rate of the disk. Video uses sustained data rates and only Disk Speed Test provides
a long burst of data for more accurate results.
When using Disk Speed Test, you need to account for disk seeking, so it’s best to add a healthy margin
to the results. If a disk array tests at 32 frames per second HD 1080, it doesn’t mean you can do 29.95 HD
capture and playback, as the margin is too tight. However it should do 24 fps ok.
Disk arrays
If you intend to run your disk array as a software stripe, you will need to make sure that ‘host RAID’ is
disabled. Use the “Disk Management” tool in “Computer Management” within Windows
™
to set up your
software RAID, or refer to third party instructions when using pre-configured hardware RAIDs.
Further information can be obtained via the Windows
™
Help and Support. Search and review the section
on “Dynamic Disks”. This section will provide you with information on how to convert a basic disk to
dynamic disk and configuration steps on striping your disk array.
Disk Management.
Disk Speed RAID results after testing a disk array.