HP XP Cache LUN Software - Manual (Page 14)

14 Cache LUN Introduction
Ending value = (↓Setting value of ending address (LBA) ÷ 512↓)
Round down the calculated value between the two down arrows (↓) after the decimal point
Setting value of ending address (LBA) is the value entered in the operations box on the Cache
LUN pane
Converted value of starting address = Starting value × 512
Converted value of ending address = ( (Ending value +1) × 512) - 1
b. Emulation types other than OPEN-V
Starting value = (↓Setting value of starting address (LBA) ÷ 96↓)
Round down the calculated value between the two down arrows (↓) after the decimal point
Setting value of starting address (LBA) is the value entered in the operations box on the Cache
LUN pane
Converted value of starting address = Starting value × 96
Converted value of ending address = ( (Ending value +1) × 96) - 1
2. Calculate the number of addresses between the starting and ending addresses calculated in step 1 .
a. OPEN-V
Number of address = Converted value of ending address - Converted value of starting address + 1
Calculate the number of LBAs used by the user data
b. Emulation types other than OPEN-V
Number of LBAs = Converted value of ending address - Converted value of starting address + 1
Calculate the number of LBAs used by the user data
Number of slots = Number of LBAs ÷ 96
Convert the number of LBAs to the number of slots
Number of addresses = Number of slots × 128
Convert the number of slots with 128 LBA
3. Calculate the required cache size according to the operation modes, or RAID levels, to use Cache
LUN XP.
a. Bind mode
RAID-1:
Required cache size = Number of addresses Ч (512 ч 16) Ч 2 ч 1,024
Units are KB
RAID types other than RAID-1:
Required cache size = Number of addresses Ч (512 ч 16) Ч 3 ч 1,024
Units are KB
b. Priority mode
Required cache size = Number of addresses Ч (512 ч 16) ч 1,024
Units are KB
Mainframe systems
To calculate the cache size for mainframe systems:
1.
Calculate the converted values of the starting and ending addresses.
For specified LDEVs:
Setting value of ending address (CC) = (↓( (LDEV size Ч 15) - 1) ч 15↓)
Round down the calculated value between the two down arrows (↓) after the decimal point
Setting value of ending address (CC) is the value that is input to the operations box in the Cache
LUN pane)
Setting value of ending address (HH) = ( (LDEV size × 15) - 1) Mod15
Remainder is the setting value of ending address (HH)