HP XP7 Owner Guide (H6F56-96006)

Table 11 System option modes (continued)
MCU/RCUDefaultDescriptionCategoryMode
high because the migration source and target are in the same
parity group or external volume group.
4. When pool shrink is performed per pool VOL from a parity
group with multiple pool VOLs defined (or from an external
volume group) while the mode is set to ON, the pool shrink
takes longer time compared to when the mode is set to OFF.
When the mode 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.)
Thin Provisioning
Fast Snap
930
* Zero data page reclamation by WriteSame and UNMAP
functions, and IO synchronous page reclamation are not disabled.
Mode 930 = ON:
All of the zero data page reclamation operations in processing
are stopped at once. (Also the zero data reclamation cannot be
newly started.)
Mode 930 = OFF (default):
The zero data page reclamation is performed.
See sheet "SOM 930" for relationship with SOM 755 and SOM
859.
Notes:
1. The mode is applied when stopping or disabling zero data
page reclamation by user request is required.
2. When the mode is set to ON, the zero data page reclamation
does not work at all.
• Zero data page reclamation by Write Same and UNMAP,
and IO synchronous page reclamation can work.
3. When downgrading micro-program to a version that does not
support the mode while the mode is set to ON, set the mode
to OFF after the downgrade
• Because the zero data page reclamation does not work at
all while the mode is set to ON.
4. The mode is related to SOM 755 and SOM 859.
By setting the mode to ON, Smart monitoring data is collected
even if the pool is a THP pool.
Thin Provisioning
Thin Provisioning Z
937
Mode 937 = ON:
Smart Tiers
Smart monitoring data is collected even if the pool is a THP pool.
Smart Tiers Z
Only Manual execution mode and Period mode are supported.
Mode 937 = OFF (default):
Smart monitoring data is not collected if the pool is a THP pool
Notes:
1. The mode is applied when Smart monitoring data collection
is required in THP environment.
2. When Smart is already used, do not set the mode to ON.
3. For Smart monitoring data collection, shared memory for Smart
must be installed.
4. If monitoring data collection is performed without shared
memory for Smart installed, an error is reported and the
monitoring data collection fails.
5. Before removeing the shared memory for Smart, set the mode
to OFF and wait for 30 minutes.
56 Functional and operational characteristics