HP P9000 Provisioning for Mainframe Systems User Guide (AV400-96369, October 2011)

For detailed information, see (page 46).
When to use Thin Provisioning Z
Thin Provisioning Z is a best fit in a mainframe environment in the following scenarios:
• Where the aggregation of storage pool capacity usage across many volumes demonstrates
largest performance optimization.
• For stable environments and large consistently growing files or volumes.
• If the application or Data Facility Storage Management Subsystem (DFSMS) does not write
over areas that are not immediately needed.
• Where the file system has a preference to write over deleted files.
Thin Provisioning Z advantages
With Thin Provisioning ZWithout Thin Provisioning ZAdvantages
You can logically allocate more capacity than
is physically installed. You can purchase less
capacity, reducing initial costs.
You must purchase physical disk capacity for
expected future use. The unused capacity adds
costs for both the storage system and software
products.
Reduces initial costs
When physical capacity becomes insufficient,
you can add pool capacity without service
interruption.
You must stop the disk array to reconfigure it.Reduces
management costs
You can allocate volumes of up to 262,668 cyl
(223.257 GB) regardless of the physical disk
As the expected physical disk capacity is
purchased, the unused capacity of the storage
Reduces
management labor
capacity. This increases the availability of
storage volumes for replication.
system also needs to be managed on the
storage system and on licensed P9500
products.
and increases
availability of
storage volumes for
replication
P9500 product licenses are based on used
capacity.
Effectively combines many applications’ I/O
patterns and evenly spreads the I/O activity
Because physical disk capacity is initially
purchased and installed to meet expected
Increases the
efficiency of the data
drive across available physical resources, preventingfuture needs, part of the data drive may not
parity group performance bottlenecks.be used. Stress of concentrating I/O loads on
Configuring the volumes from multiple parityjust a subset of the storage may decrease
performance. groups improves parity group performance. This
also increases storage use while reducing power
and pooling requirements (total cost of
ownership).
Thin Provisioning Z advantage example
To illustrate the merits of a Thin Provisioning Z environment, assume you have 12 LDEVs from 12
RAID 1 (2D+2D) array groups assigned to a THP pool. All 48 disks contribute their IOPS and
throughput power to all THP volumes assigned to that pool. If more random read IOPS horsepower
is desired for a pool, then it can be created with 32 LDEVs from 32 RAID 5 (3D+1P) array groups,
thus providing 128 disks of IOPS power to that pool. Because up to 1024 LDEVs may be assigned
to a single pool, this represents a considerable amount of I/O power under (possibly) just a few
THP volumes.
This type of aggregation of disks was possible previously only by using expensive and somewhat
complex host-based volume managers on the servers.
Thin Provisioning Z example
The following figure illustrates the difference between storage purchases made before and after
installing Thin Provisioning Z software.
Thin provisioning 11