Memory Operation; Data Protection - Hitachi G1000 Hardware Manual

# of controller chassis
Item
2 & 3 Main (required) cache path control
adapters
1 & 2 Cluster 1

Memory operation

The controller places all read and write data into the cache. The amount of
fast-write data in cache is dynamically managed by the cache control
algorithms to provide an optimum amount of read and write cache,
depending on the workload read and write I/O characteristics.

Data protection

The VSP G1000, VSP G1500, and VSP F1500 storage systems are designed to
protect the loss of data or configuration information stored in the cache when
electrical power fails. The cache is kept active for up to 32 minutes by the
cache backup batteries while the system configuration and data are copied to
the cache flash memory in the cache backup modules. For more information,
see
page
44
Hitachi Virtual Storage Platform G1000, G1500, and Virtual Storage Platform F1500 Hardware Guide
configuration
2. HDS minimum cache per system is 64 GB whether configured with one or two controllers.
Description
Cache flash memory on page
112.
Maximum cache capacity configurable based on
the number of cache path control adapter pairs
Capacity of cache
memory module
1 cache path control
adapter pair (Included
Item
1 & 4 Optional cache path control adapters
3 & 4 Cluster 0
48, and in
Introduction
included:
2 cache path control
adapter pairs (One
controller and an
with controller)
additional feature
Description
Battery backup operations on
included with
added)