Compaq External RAID Controller & Subsystem Infortrend, Руководство по эксплуатации

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Infortrend
7-4
display the current setting with the Write-Back caching. Choose Yes
in the dialog box that follows to confirm the setting.
The Write-through mode is safer if your controller is not configured
in a redundant pair and there is no battery backup.
Write-back caching can dramatically improve write performance by
caching the unfinished writes in memory and let them be committed
to drives in a more efficient manner. In the event of power failure, a
battery module can hold cached data for days. In the event of
controller failure, data cached in the failed controller has an exact
replica on its counterpart controller and therefore remains intact.
IMPORTANT!
• The original 512GB threshold on array optimization mode is canceled. If the
size of an array is larger than 16TB, only the optimization for sequential I/O
can be applied. Logical drives of this size are not practical; therefore, there is
actually no limitation on the optimization mode and array capacity.
• Every time you change the Caching Parameters, you must reset the
controller for the changes to take effect.
• In the redundant controller configuration, write-back will only be applicable
when there is a synchronized cache channel between partner controllers.
7.3 Viewing the Connected Drives
Prior to configuring disk drives into a logical drive, it is necessary to
understand the status of physical drives in your enclosure.
Use arrow keys to scroll down to “View and Edit SCSI Drives.” This
will display information of all the physical drives installed.