HP XP Array Manager Software - Manual (Page 17)

About Cache Manager Operations 2-3
Hitachi Cache Manager User’s Guide
Maximum number of resident
extents Logical Volume:
≤ 1024 extents
Storage System:
≤ 1024 extents USP V:
Logical Volume: ≤ 4096 extents
Storage System: ≤ 16384 extents
USP:
Logical Volume: ≤ 4096 extents
Storage System: ≤ 4096 extents
Maximum number of extents for
dataset statistics information Logical Volume:
≤ 64 extents
Storage System:
≤ 64 extents USP V:
Logical Volume: ≤ 64 extents
LCU: ≤ 64 extents
Storage System: ≤ 32640 extents
USP:
Logical Volume: ≤ 64 extents
Storage System: ≤ 64 extents
Maximum available size of cache
memory for Cache Residency
Manager.
Note: The Maximum number of
extents for dataset statistics
information (see row above)
determines the maximum
available size of cache memory
for Cache Residency Manager. Additional cache memory size for Cache Residency
Manager:
Resident 256 MB area actually occupies 512 MB cache
memory in RAID-1 or 768 MB in RAID-5/6.
Unit to specify to reside 1 track
Minimum / Maximum size of
cache residence 1 track / logical volume size
DKC Software/
Cache Residency
Manager
Specifications
Additional cache memory module Mandatory
Units Used to Specify Data for Cache Storage CCH, VTOC, VTOC
Index
The Cache Manager function for the RAID storage systems is similar to the
Cache Residency function; it allows you to store specific data in cache
memory. However, where Cache Residency only allows you to specify what
data to place in cache by using the physical address (CCHH), Cache Manager
allows you to specify the data to be placed into cache by CCHH, VTOC, VTOC
index, VVDS (VSAM volume dataset) or the extent of the dataset area. Data to
be removed from cache may be specified by dataset name, VTOC, VTOC
Index, VSAM volume dataset (VVDS), or by volume. If you set the cache area
from Storage Navigator, you must define the extent using CCHH.
Cache Manager also allows you to coordinate objective jobs with other
functions, and to control jobs dynamically and automatically, thereby
increasing efficiency and improving system performance.