Silicon Graphics InfiniteStorage 4000 Series System Upgrade Manual page 63

Chapter 2: Upgrading Trays in the Storage Array
Follow this procedure only if you upgraded the cache memory DIMMs from 6 GB to
12 GB. If you upgraded the cache memory DIMMs from 12 GB to 24 GB, you can
skip this procedure.
NOTE On the E5460 controller canister, the total cache backup memory per controller
does not equal the total cache memory per controller.
The following table lists the cache backup memory device configurations.
Total Cache Memory per
Controller
6 GB
12 GB
24 GB
NOTE Although the physical capacity of each cache backup memory device is 8 GB,
only 4 GB of each device is used for nonvolatile cache memory offload. The remainder
is used for other purposes, such as storing controller firmware images. The storage
array profile displays the capacity of each cache backup memory device as 4 GB.
Number of Cache Backup
Memory Devices per
Controller
1
2
2
Cache Backup Memory
Device Slots Populated
1
1, 2
1, 2
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