Cache Residency System Specifications; Estimating Cache Size For Cache Residency - HPE XP7 User Manual

prestage function, the cache hit is available from the first host access, further improving data
access performance. Prestaging can be used for both priority mode and bind mode operations.
Prestaging occurs under any of the following circumstances:
When prestaging is performed using Cache Residency.
When the storage system is powered on.
When cache maintenance is performed.

Cache Residency system specifications

Item
Supported device emulation
types
Supported volume types
Unit of cache area allocation
Number of cache areas

Estimating cache size for Cache Residency

This section describes and provides instructions for calculating the cache size required for Cache
Residency operations on your XP7 Storage system.
"Cache Residency cache areas" (page 141)
"Cache size requirements" (page 141)
"Calculating cache size for open systems" (page 141)
"Calculating cache size for mainframe systems" (page 143)
140 Cache Residency operations
Specification
Open system
OPEN-V
OPEN-3, 8, 9, E, K, L
Virtual LUN
For OPEN-V, at least 512 LBAs:
Equivalent to 264 KB
For other than OPEN-V, at least 96
LBAs: Equivalent to 66 KB
Per storage system: 16,384
Per LDEV: 4,096
Mainframe system
3390-1, 2, 3, 9, A, L, M
3390-3A, 3B, 3C
3390-9A, 9B, 9C
3390-LA, LB, LC
3390-MA, MB, MC
Virtual LVI
At least one cache slot (or track): Equivalent
to 66 KB.
Up to 1 LDEV.