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Physical Parameters
When you select Physical Parameters, a menu similar to the following displays. The three
physical parameters that can be set are Default rebuild rate, the Stripe size (K bytes), and
Controller read ahead. Use the arrow keys to select a parameter, and press
ENTER
to toggle
the settings.
Physical Parameters
Default Rebuild Rate
50
Stripe Size (K bytes)
8
Controller read ahead
Enabled
NOTE
The default physical parameters are: Default rebuild rate = 50, Stripe size (K bytes) = 8,
Controller read ahead = Enabled.
Use the Default rebuild rate option to change the rebuild rate from 0 to 50. A rebuild rate of
50 is the maximum. A higher value assigns a higher priority to the rebuild activity rather
than the other activities, resulting in a faster drive rebuild, but slower disk performance. If
the rebuild needs the least priority, set the rebuild rate to 0 to increase performance for other
activities.
The Stripe size (K bytes) option changes the way of accessing the information on the drives.
Stripe sizes of 8K, 16K, 32K and 64K are supported. A higher stripe size results in a higher
sequential throughput and a slightly reduced random throughput.
WARNING
When you select a different stripe size, all existing data on the drives will be lost.
Back up the drives before changing the stripe size.
The Controller read ahead option, when set to Enabled, directs the controller to read the data
from the block requested and from one block ahead. This method of reading data assumes
that the subsequent block of data will soon be requested. The Controller read ahead option is
Enabled by default and will increase the performance of read operations.
SCSI Xfr Parameters
The SCSI Xfr Parameters menu allows you to change Data transfer rate and Command
tagging parameters for each channel on the current RAID controller board. When you select
the SCSI Xfr Parameters from the Edit/View Parameters menu, you are prompted to select a
channel. After selecting the channel, the following menu displays.
Summary of Contents for InterRAID-12
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