Hitachi VSP G200 System Administration Manual page 370

Mode Category
867 Dynamic
Provisioning
Dynamic Tiering
896 Dynamic
Provisioning
Dynamic Tiering
Thin Image
370
System Administrator Guide for VSP Gx00 models and VSP Fx00 models
Description
Mode 857 = ON: The cache allocation capacity is limited to
within the prescribed capacity*.
Mode 857 = OFF (default): The cache allocation capacity is
not limited to within the prescribed capacity*.
*Prescribed capacity:
• VSP G800, VSP, HUS VM: 128 GB
• VSP G400, G600: 64 GB
• VSP G200: 16 GB
Notes:
1. This SOM is applied to stabilize the performance by
preventing paging of PM control information from
occurring. For details, refer to the section of Virtual
Partition Manager in the guideline.
2. The cache hit rate may decrease.
3. The cache allocation capacity per MPB/MPU is limited to
within the prescribed capacity.
All-page reclamation (discarding all mapping information
between DP pool and DP volumes) is executed in DP-VOL
LDEV format. This new method is enabled or disabled by
setting this SOM to ON or OFF.
Mode 867 = ON (default*): LDEV format of the DP-VOL is
performed with page reclamation.
Mode 867 = OFF:LDEV format of the DP-VOL is performed
with 0 data writing.
*The default is OFF for VSP, HUS VM, and VSP Gx00 models
and VSP Fx00 models with firmware 83-03-xx and earlier.
Notes:
1. This SOM is applied from factory shipment.
2. Do not change the setting of this SOM during DP-VOL
format.
3. If the setting of this SOM is changed during DP-VOL
format, the change is not reflected to the format of the
DP-VOL being executed but the format continues in the
same method.
This SOM enables or disables the background format function
performed on an unformatted area of a DP/DT/TI pool.
For information regarding operating conditions, see the
Provisioning Guide for your storage system.
Mode 896 = ON: The background format function is
disabled.
Mode 896 = OFF (default): The background format
function is enabled.
Notes:
1. This SOM is applied when a customer requires the
background format for a DP/DT/TI pool in the
environment where new page allocation (in the case
that system files are created from a host for newly
created multiple DP-VOLs, for example) frequently
System option modes
Default MCU/RCU
ON -
OFF -