Journal groups – HP XP Continuous Access Software User Manual
Page 44
NOTE:
If you use LUSE volumes, you must add 1 to the value calculated by the above formula.
•
Maximum number of pairs that can be created:
Use the following formulas to calculate the maximum number of pairs you can create:
◦
When one pair of extended shared cache memories is used
Maximum number of pairs = ( (11,605 /Number of bitmap areas) )
The ... symbols around a value indicate the value should be rounded down to the nearest
integer.
◦
When two pairs of extended shared cache memories are used
Maximum number of pairs = ( (28,671 /Number of bitmap areas) )
The ... symbols around a value indicate the value should be rounded down to the nearest
integer.
CAUTION:
Bitmap areas used for XP Continuous Access Journal are also used for XP
Continuous Access. If you use XP Continuous Access and XP Continuous Access Journal,
use the total number of both pairs.
NOTE:
If the calculated maximum number of pairs exceeds 16,384, the actual maximum
number of pairs is limited to 16,384.
NOTE:
The capacity of OPEN-V is variable. To calculate the maximum number of pairs
for OPEN-V, use the formula.
Journal groups
XP Continuous Access Journal journal groups have the following requirements:
•
Each XP Continuous Access Journal pair must be assigned to one and only one journal group.
•
lists journal group specifications.
Table 13 Journal group specifications
Support specifications
Item
Up to 256 journal groups (No. 0 - 255) per array if all
the following conditions are satisfied:
◦ Array is an XP12000 (not an XP10000).
◦ Microprogram version is 50-05-00-00 or later.
◦ Shared memory options #3, #4, and #5 are already
installed.
◦ High Performance mode is applied to shared
memories
1
.
NOTE:
Only the HP service engineer can install shared
memory options and apply High Performance mode. If
necessary, contact your HP account support
representative.
Up to 16 journal groups (No. 0 - 15) per array if any
of these conditions are not satisfied.
Number of journal groups
Up to 4,096
Number of data volumes in a journal group
44
XP Continuous Access Journal operations requirements and restrictions