Hitachi VSP F400, System Administration Manual

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• Savings %: Displays the percentage of the capacity reduced by data
compression with respect to the used capacity before the data
compression. This will not display a value until data is compressed.
If the savings percentage for a pool is not high enough, you can provision
additional pool volumes to the pool from the parity groups using FMD DC2
drives.
Creating a pool
Use the basic option to take advantage of tiers that are based on best
practices.
If you want more flexibility and do not need to take advantage of best
practices, you can use the advanced option to select specific parity groups.
You cannot create pools on external parity groups. They must be created
outside Storage Advisor.
The following types of pools are identical:
• Thin = HDP (Dynamic Provisioning), which is functionality that allocates
virtual volumes to a host and uses the physical capacity that is necessary
according to the data write request.
• Tiered = HDT (Dynamic Tiering), which is used with Dynamic Provisioning
and places data in a hardware tier according to the I/O load. For example,
a data area that has a high I/O load is placed in a high-speed hardware
tier, and a data area that has a low I/O load is placed in a low-speed
hardware tier.
• Snap = HTI (Thin Image), which stores snapshot data in pools. A pool
consists of multiple pool-VOLs. The pool-VOLs contain the snapshot data. A
pool can contain up to 1,024 pool-VOLs.
Pools inventory
Access the Pools page to add, update, and delete pools.
From the dashboard, click Storage Systems and then click a storage system
tile to view parity groups, pools, volumes, and ports.
Click Pools to view the inventory of pools.
Note: If there are external pools (on external storage), they display in Pools
inventory, but they cannot be added, updated, or deleted.
Configuring the storage system 77
System Administrator Guide for VSP Gx00 models and VSP Fx00 models