Hitachi Virtual Storage Platform, Руководство пользователя и справочник

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Functional and Operational Characteristics
2–27
Hitachi VSP User and Reference Guide
690 Universal
Replicator,
Universal
Replicator for
Mainframe This option is used to prevent Read JNL or JNL
Restore when the Write Pending rate on RCU
exceeds 60% as follows:
•
When CLPR of JNL-Volume exceeds 60%, Read
JNL is prevented.
• When CLPR of Data (secondary)-Volume
exceeds 60%, JNL Restore is prevented.
Mode 690 = ON:
Read JNL or JNL Restore is prevented when the
Write Pending rate on RCU exceeds 60%.
Mode 690 = OFF (default):
Read JNL or JNL Restore is not prevented when the
Write Pending rate on RCU exceeds 60% (the same
as before).
Notes:
1. This mode can be set online.
2. This mode should be set per customer’s
requests.
3. If the Write Pending status long keeps 60% or
more on RCU, it takes extra time for the initial
copy to be completed by making up for the
prevented copy operation.
4. If the Write Pending status long keeps 60% or
more on RCU, the pair status may become
Suspend due to the JNL-Vol being full.
OFF .
696 Open This mode is available to enable or disable the QoS
function.
Mode 696 = ON:
QoS is enabled. (In accordance with the Share value
set to SM, I/Os are scheduled. The Share value
setting from RMLIB is accepted)
Mode 696 = OFF (default):
QoS is disabled. (The Share value set to SM is
cleared. I/O scheduling is stopped. The Share value
setting from host is rejected)
Note:
1. Set this mode to ON when you want to enable the
QoS function.
OFF .
Mode Category Description Default MCU/RCU