HP XP P9500 Storage - Manual (Page 64)

Requirements Items
This setting can restore the ability to shrink the pool, create the THP V-VOL, and expand the THP
V-VOL.
Utilization thresholds • Warning Threshold: You can set the value between 1% and 100%, in 1% increments. The
default is 70% (recommended).
•
Depletion Threshold: You can set the value between 1% and 100%, in 1% increments. The
default is 80%.
Pool usage over either threshold will cause a warning to be issued via a SIM reported to Remote
Web Console and an SNMP trap reported to the open-systems host
42 MB Data allocation unit
(page)
The 42-MB page corresponds to a 42-MB continuous area of the THP V-VOL. Pages are allocated
only when data has been written to the area of the THP V-VOL.
Defined based on the media type (see Drive type for a Smart Tiers tier, below). Maximum 3
tiers. Tier
(Smart Tiers)
No specific limit. Pool capacity is limited to 1.1 PB. Also, total of all pool capacity is limited to
1.1 PB. Maximum capacity
of each tier
(Smart Tiers)
Pool-VOL requirements
Pool-VOLs make up a THP-pool.
Requirements Items
Logical volume (LDEV) Volume type
For best performance, pool-VOLs for a pool should not share a parity group with other volumes.
Pool-VOLs cannot be used for any other purpose. For instance, you cannot specify the following
volumes as Thin Provisioning pool-VOLs:
• Volumes used by Business Copy, Auto LUN, Continuous Access Synchronous, External Storage
Access Manager, or Continuous Access Journal
•
LUSE volumes
• Volumes defined by Cache Residency Manager
•
Volumes already registered in Snapshot or Thin Provisioning pools
•
Volumes used as Snapshot P-VOLs or S-VOLs
• Data Retention volumes with a Protect, Read Only, or S-VOL Disable attribute
•
Volumes whose LDEV status is other than Normal or Normal (Quick Format)
You cannot specify volumes in blocked status or volumes in copying process.
•
System disks
•
Command devices
• Quorum disks
OPEN-V Emulation type
Any RAID levels can be used for pool-VOLs. RAID 5, RAID 6, and the external volume can
coexist in the same pool. RAID level for a Thin
Provisioning pool
For pool-VOLs in a pool:
•
RAID 6 is the recommended RAID level for pool-VOLs, especially for a pool where the recovery
time of a pool failure due to a drive failure is not acceptable.
• Pool-VOLs of the same drive type must also have the same RAID level.
•
Pool-VOLs on external volumes cannot have a mix of cache modes set to enable and disable.
64 Configuring thin provisioning