Hitachi Command Suite 8 User Guide

DP pools are created by Device Manager, which automatically selects volumesbased on user-specified conditions. Users can also directly specify parity groups to create a DP pool.
Users can also specify settings such as values for the usage rate threshold and reservation threshold.
If you have registered a Tiered Storage Manager license, you can use the
Mobility tab to evaluate and analyze the operation status that is related to a DP pool. When you delete an unnecessary DP pool, DP volumes created fromthat...

Creating a DP poolYou can create an HDP or HDT pool, which provides more efficient use ofphysical storage for virtual volumes that are allocated to hosts from the DPpool. DP pool performance can be improved if you use the entire capacity of a
parity group for a single DP pool.
Prerequisites
• Register the target storage system. • When defining an external LDEV tier rank, externally connect a storage system that has multiple performance levels.
• Verify the following when using Hitachi USP V/VM, Virtual...

b.(Optional) Select 'Allow to mix different drive types/speeds, chip
types, RAID levels or volume locations' to allow combining resources
with different characteristics.
c. Select one or more parity groups, and click  Add to Pool and then
Close . The Pool Summary  information is updated.
d. (Optional) Click  Advanced Options  to configure Pool ID, Used
Threshold, Subscription Thresholds, and DP volume protection options,
as needed.
e. Go to step 7.
4. To configure an HDT pool, select a  Pool Type...

b.For mixed mode in the  Internal Parity Groups  tab or the External
Parity Groups  tab, select parity groups that you want to add to the
HDT pool, click  Add to Pool, and click Close. The Tier Configuration
table in Pool Summary shows the new tier configuration status for
each tier.
c. Click  Advanced Options  to configure Pool ID, Used Threshold,
Subscription Thresholds, and DP volume protection options, as needed.
d. Click  HDT Options , and configure the tier management options as
needed.
e. Go to...

As you enter information in a dialog box, if the information is incorrect, errors
that include a description of the problem appear at the top of the box.
Table 5-4  Create Pool dialog boxFieldSubfieldDescriptionStorage
System-Displays the selected storage system name, or prompts you to select the
storage system from a list.Pool Name-Accept the default pool name, or enter a pool name. Do not confuse pool name
with pool ID. The pool ID is an assigned number, the pool name is a user-
definable value....

FieldSubfieldDescriptionFor an HDT pool, when the Internal Parity Groups tab is selected, the Available
Parity Groups table lists parity group, drive type, drive speed, chip type, RAID level, total capacity, unallocated capacity, free capacity, number of volumes,
CLPR, cache mode, and resource group. When the External Parity Groups tab is
selected, the Available Parity Groups table lists parity group, total capacity,
unallocated capacity, free capacity, number of volumes, CLPR, external storage
system,...

FieldSubfieldDescriptionallocation is still allowed (this is a soft limit). Alerts display on the Dashboardand the Tasks & Alerts tab.LimitExceeding the subscribed limit threshold (as a percentage of DP pool capacity)generates an alert, an email, or both. However, if volume allocation will exceed
the subscribed limit threshold, volume allocation is not allowed (this is a hard limit). You must either reduce the capacity of the volume you want created, or increase the subscription limit.Protect DP VOL...

FieldSubfieldDescriptionMonitoring mode
PeriodicPeriodic monitoring mode uses performance data from the last monitoring cycle (see Cycle time). Tier relocation responds immediately to workload changes.
This mode is a more aggressive tier relocation monitoring mode.Relocation SpeedFor the VSP G1000, you can select one of five speeds for the relocation of pages in a pool, in a unit of time, from 1 (slowest) to 5 (fastest). The default is 3
(standard). To reduce the load on the storage system, specify a...

If you configured HDT pool tiers to be managed automatically usingElement Manager, you can also verify the following:
• Monitoring Information
• Last Monitoring Start Date
• Last Monitoring End Date • Monitoring Status• Relocation Status• Relocation Progress (%)
Related concepts
•
About virtualizing storage capacity  on page 160
Related tasks •
Creating a DP pool  on page 162
Expanding DP pools Pool capacity can be increased by expanding DP pools or by converting HDP
pools into HDT pools.
Expand a DP...

Note: In HDP pools, if different drive types and/or RAID levels are mixed in
an HDP pool, I/O performance will be dependent on the drive type
characteristics and RAID level on which any given page resides.
Procedure
1. On the  Resources  tab, expand the storage systems, select an HDP pool
on the target storage system, and click  Expand Pool.
2. To expand an HDP pool:
a. In Additional Parity Groups, click  Add Parity Groups.
b. Select one of more parity groups, click  Add to Pool, and then click
Close ....