HP XP P9500 Storage - Manual (Page 57)

Requirements Items
• Pool-VOLs of the same drive type with different RAID levels can coexist in the same pool.
Note that HP recommends that you use the following configuration:
◦
If there are pool-VOLs of the same in a tier, unify the RAID levels.
◦
Although you can set four or more of hard disk drive types for pool-VOLs in the same
pool, you should use three or fewer types.
◦
Because the speed of RAID 6 is slower than other RAID levels, tiers that use other RAID
levels should not be placed under a tier that uses RAID 6.
• If pool-VOLs are external volumes, set the cache mode to Enable.
SAS15K, SAS10K, SSD, SAS7.2K, and SSD. Hard disk drive for a
Thin Provisioning Z
pool
Up to three different drive types of pool-VOLs can be registered in the same pool.
Cautions:
•
If multiple pool-VOLs with different drive types are registered in the same pool, the I/O
performance depends on the drive type of the pool-VOL to which the page is assigned.
Therefore, if different drive types are registered in the same pool, ensure that the required
I/O performance is not degraded by using less desirable drive types.
•
Unless intentionally transitioning between SATA drive types, a SATA-E volume and a
SATA-W/V volume should not coexist in a pool.
•
RAID 1 pool-VOLs with SATA-E drive types cannot be registered in a pool.
SAS15K, SAS10K, SAS7.2K, SSD, and the external volume can be used as the hard disk drive
type. These hard disk drive types can coexist in the same pool. Hard disk drive type
for a Smart Tiers Z
pool
Cautions:
•
It is recommended that the SATA-E volume and SATA-W/V volume do not coexist in one
pool.
• RAID 1 pool-VOLs with SATA-E drive types cannot be registered in a pool.
Internal volume: From 8 GB to 695 GB (from 9,676 cyl to 837,760 cyl). Volume capacity
External volume: From 8 GB to 927 GB (from 9,676 cyl to 1,117,760 cyl).
A volume whose capacity is less than 8GB (9,676 cylinders) cannot be a pool volume.
You must format the LDEV before the volume is registered in a pool. You cannot format an LDEV
once it is a pool-VOL. LDEV format
THP V-VOL requirements
Requirements Items
THP V-VOL (V-VOL) Volume type
The LDEV number is handled in the same way as for normal volumes.
3390-A Emulation type
Up to 63,232 per system. Any number of available THP-VOLs can be associated with a pool. Maximum number of
THP V-VOLs
Up to 63,232 volume groups per system. If external volumes and V-VOLs are used, the total
number of external volumes and V-VOLs must be 63,232 or less.
For 3390-A, volume capacity from 1 cyl to 262,668 cyl per volume. Volume capacity
Available (Quick Format is not available.) LDEV format
When you format an LDEV on the THP V-VOLs, the storage system initializes data only in the
consumed pool pages of the THP V-VOLs. However, after you format an LDEV, the free space
in the pool does not increase because the pages are not released.
When you format an LDEV on the THP V-VOLs, the storage system reclaims the consumed pool
pages of the THP V-VOLs.
Thin provisioning requirements 57