HP P9000 Provisioning for Open Systems User Guide (AV400-96396, October 2011)

• The capacity to be added to the THP V-VOL must be specified within the range indicated
below LDEV Capacity in the Expand V-VOLs window.
• You cannot add capacity to the THP V-VOL unless the pool related to the target THP V-VOL is
in any one of the following statuses:
◦ Normal
◦ Exceeding subscription limit threshold
◦ In progress of pool capacity shrinking
CAUTION: When increasing THP V-VOL capacity, do not perform the following operations. Also,
when performing these operations, do not increase THP V-VOL capacity.
• Operations using Virtual LUN
• Operations using Cache Residency
• Creating THP V-VOLs
• Restoring pools
• Deleting THP V-VOLs
• Operations to increase the THP V-VOL capacity in another instance of RAID Manager
• Maintenance of your storage system
After increasing THP V-VOL capacity, click Refresh in Remote Web Console, and then confirm that
the THP V-VOL is increased. If the THP V-VOL capacity is not increased, wait a while, click Refresh
again, and confirm that the THP V-VOL is increased. If you perform a Remote Web Console
operation without making sure that the THP V-VOL is increased, operations from Remote Web
Console can fail.
If either of the following operations is being performed, the THP V-VOL capacity might not be
increased:
• Auto LUN
• Quick Restore by Business Copy
Operating system and file system capacity
Operating systems and file systems when initializing a P-VOL will consume some Thin Provisioning
pool space. Some combinations will initially take up little pool space, while other combinations
will take as much pool space as the virtual capacity of the THP V-VOL.
The following table shows the effects of some combinations of operating system and file system
capacity. For more information, contact your HP representative.
Pool Capacity ConsumedMetadata WritingFile SystemOS
Small (one page)Writes metadata to first block.NTFSWindows Server
2003 and Windows
Server 2008*
If file update is repeated, allocated
capacity increases when files are
deleted or added, therefore the
effectiveness of reducing the pool
capacity consumption decreases.
Depends upon allocation group size.
The amount of pool space consumed
Writes metadata in Allocation
Group Size intervals.
XFSLinux
will be approximately [THP V-VOL
Size]*[42 MB/Allocation Group Size]
About 33% of the size of the THP
V-VOL.
Writes metadata in 128-MB
increments.
Ext2
Ext3
Thin provisioning requirements 67