Hitachi VSP G400 - Page 374

Mode Category Description Default MCU/RCU
actual I/O value (total number of I/Os of all tiering
policies) < performance potential value of Tier1* × 0.6
* The performance potential value of Tier1 displayed on
Monitor information by using Dx-ray.
For more details about the interactions between SOMs 897,
898, and 901, contact customer support (see
SOM897_898_901 sheet).
904 Dynamic Tiering By setting this SOM to ON or OFF, the number of pages to be
migrated per unit time at tier relocation is changed.
Mode 904 = ON: The number of pages to be migrated at
tier relocation is set to up to one page per second.
Mode 904 = OFF (default):No restriction on the number of
pages to be migrated at tier relocation (existing
specification).
Notes:
1. This SOM is applied when the requirement for response
time is severe.
2. The number of pages to be migrated per unit time at
tier relocation decreases.
OFF -
908 Universal
Replicator
This SOM can change CM capacity allocated to MPBs with
different workloads.
Mode 908 = ON: The difference in CM allocation capacity
among MPBs with different workload is large.
Mode 908 = OFF (default): The difference in CM allocation
capacity among MPBs with different workload is small
(existing operation) .
Notes:
1. If a CLPR is used by only some MPBs among all the
installed MPBs, set this SOM to ON for the CLPR to
increase CM capacity allocated to the MPBs that use the
CLPR.
Example:
(a) A CLPR only for UR JNLG.
(b) A configuration where MPBs and CLPRs are
separately used for Open and Mainframe systems.
2. Since CM capacity allocated to MPBs with low load is
small, the performance is affected by a sudden increase
in load.
3. SOM 908 cannot be used with SOM 933. When SOM
933 is set to ON, the function of SOM 908 is canceled
even though SOM 908 is ON.
4. This SOM is effective for a CLPR. Therefore, when
setting this SOM to ON/OFF, select target "LPRXX
(XX=00 to 31)". For example, even when CLPR0 is
defined (any of CLPR1 to 31 are not defined), select
“LPR00” first and then set this SOM to ON/OFF.
OFF
Both
930 Dynamic
Provisioning
Dynamic Tiering
When this SOM is set to ON, all of the zero data page
reclamation operations in processing are stopped. (Also the
zero data page reclamation cannot be started.)
OFF -
374 System option modes
System Administrator Guide for VSP Gx00 models and VSP Fx00 models