Hitachi Virtual Storage Platform, User And Reference Manual

Page: 54 / 146

Hitachi VSP User and Reference Guide
2–26
Functional and Operational Characteristics
689 TrueCopy for
Mainframe
ShadowImage
for Mainframe This option is used to slow down the initial copy and
resync copy operations when the Write Pending rate
on RCU exceeds 60%.
Mode 689 = ON :
The initial copy and resync copy operations are
slowed down when the Write Pending rate on RCU
exceeds 60%.
*: From RAID700, if the Write Pending rate of CLPR
where the initial copy target secondary volume
belongs to is not over 60% but that of MP PCB
where the S-VOL belongs to is over 60%, the initial
copy operation is slowed down.
Mode 689 = OFF (default):
The initial copy and resync copy operations are not
slowed down when the Write Pending rate on RCU
exceeds 60% (the same as before).
Note:
1. 1. This mode can be set online.
2. 2. The micro-programs on both MCU and RCU
must support this mode.
3. 3. This mode should be set per customer’s
requests.
4. 4. If the Write Pending status long keeps 60%
or more on RCU, it takes extra time for the
initial copy and resync copy to be completed by
making up for the slowed down copy operation.
5. 5.From RAID700, if the Write Pending rate of
CLPR where the initial copy target secondary
volume belongs to is not over 60% but that of
MP PCB where the S-VOL belongs to is over
60%, the initial copy operation is slowed down.
OFF .
Mode Category Description Default MCU/RCU