HP XP Racks - Manual (Page 97)

About optimizing storage
HP StorageWorks P9000 Command View Advanced Edition Suite allows you to manage storage by
allocating volumes, expanding tiers and THP/Smart pools, and performing migration, based on
information acquired from checking summaries, alerts, performance statistics, and the operating status
of storage resources. Common storage optimization issues include:
• If used capacity for a THP/Smart pool has reached a threshold, or if a volume that satisfies a ca-
pacity requirement cannot be created or assigned because the unused capacity is insufficient,
add THP/Smart pool volumes to increase the capacity of the THP/Smart pools.
• If the performance of a THP/Smart pool has decreased and data I/O is slow, add more THP/
Smart pool volumes to distribute loads within the THP/Smart pools. Another option is to perform
volume migration to distribute I/O loads on the THP/Smart pools.
• When using the Smart pool, performance problems may occur at certain times. Ensure that monit-
oring occurs during periods when I/O loads are occurring. You can:
• Start or stop the monitoring/relocation process manually in accordance with known times for
load changes.
• Cancel the monitoring process during periods of low activity.
• If Smart volume applications switch between online and batch processing, it can be helpful to
save optimized volume data placements, by processing method, as profiles. By applying the cor-
responding profile before beginning processing, the data placement that fits the characteristics of
the processing method is restored.
• When using Smart pools, you want to prioritize the data relocation of Smart volumes for which
capacity and access patterns vary widely, but I/O operations decrease without relocating effect-
ively. You can disable the relocation of Smart volumes for which the current data location presents
no problems, to reduce relocation load.
• When using Smart pools, important data is allocated to the lower hardware tier because it has
fewer I/O accesses. To prevent unwanted relocations, set a specific hardware tier for the Smart
by configuring the tiering policy.
• If the load on a volume is too high when volume data is backed up to tape, create a copy pair
for the volume. Then do a tape backup by using the copied volume (as a secondary volume).
• If it's not possible to assign a high-performance volume to a host because all unassigned volumes
are low performance, perform volume migration so that less frequently used data is migrated to
a low-performance volume, and then assign the now available high-performance volume to an
appropriate host.
User Guide 97