Mylex eXtremeRAID 1100, Installation Manual

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DMM1100 Operation
A-2 eXtremeRAID Installation Guide
DMM1100 Operation
This DMM1100 consists of 16 MB, 32MB, or 64MB of SDRAM cache
memory, a rechargeable nickel-cadmium battery, a charging circuit, and
power monitoring circuitry. The controller is shipped with the DMM1100
installed, and will not function without it.
Battery Conditioning Prior to Use
Battery conditioning is automatic. There are no manual procedures for
battery conditioning or preconditioning to be performed by the user.
Set-up – Enabling the Write-Back Cache
Maximum RAID performance is achieved when the cache is in write-back
mode. The write-back cache is enabled by toggling the write-back/write-
through mode switch. The write-back/write-through mode switch is accessed
using RAID EzAssist (the BIOS Configuration Utility), or in GAM. Refer to
the RAID EzAssist Configuration Utility User Reference Guide or the Global
Array Manager Client Software Installation Guide and User Manual for
instructions on how to examine and change the mode switch.
Battery Backup Capacity
The battery backup’s capacity varies with the cache memory capacity used.
In the event of a power failure, the battery backup can be expected to
maintain cache data integrity for the periods of time shown in Table A-1.
Maintenance
No maintenance is required. It is recommended that the DMM1100 charge
level be periodically checked using the Gas Gauge function in GAM (see the
Global Array Manager Client Software Installation Guide and User
Manual).
Table A-1. Battery Backup Capacity
Memory Size Approximate Battery Charge Life
64MB 48 hours
32MB 72 hours
16MB 72 hours