Hitachi AMS 2100, Hardware Manual

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Introduction
Hitachi AMS 2100/2300 Storage System Hardware Guide
Cache specifications
The Cache specifications are shown in Table 1-9 .
Performance reporting and monitoring
The Navigator 2 storage management software provides the capability to
either monitor the disk array in real-time or collect historical data regarding
the performance of the storage system.
Table 1-9: Cache Specifications
Item Description
AMS 2100
Capacity (MB per
controller) 2,048, 4,096
Control method Read LRU / Write After
1
Battery backup Provided
Backup duration (h)
2
48 hrs when cache is 8,192 MB (4,096 MB per controller)
72 hrs when cache is 4,096 MB (2,048 MB per controller)
AMS 2300
Capacity (MB per
controller) 4,096, 8,192 MB
Control method Read LRU / Write After
1
1. LRU = Least Recently Used. An algorithm where new items are placed at the
top of the cache and items at the bottom of the cache are discarded when the
cache grows past its size limit. Whenever an item is accessed, it is pulled back
to the top of the cache.
Battery backup Provided
Backup duration (h)
2
2. Backup time in hours with two full charged cache backup batteries.
24 hrs when cache is 16,384 MB (8,192 MB per controller
36 hrs when cache is 8192 MB (4,096 MB per controller)