Storage Pools - IBM Storwize V5010 Manual

1.6.8 Storage pools

storage pool
A
to provide capacity for volumes. All MDisks in the pool are split into extents of the same size.
Volumes are then allocated out of the storage pool and are mapped to a host system.
MDisks can be added to a storage pool at any time to increase the capacity of the pool.
MDisks can belong in only one storage pool. For more information, see Chapter 4, "Storage
pools" on page 143.
Each MDisk in the storage pool is divided into a number of extents. The size of the extent is
selected by the administrator when the storage pool is created and cannot be changed later.
The size of the extent ranges from 16 MB - 8 GB.
Default extent size: The GUI of IBM Storwize V5000 Gen2 has a default extent size value
of 1024 MB when you define a new storage pool.
The extent size directly affects the maximum volume size and storage capacity of the
clustered system.
A system can manage 2^22 (4,194,304) extents. For example, with a 16 MB extent size, the
system can manage up to 16 MB x 4,194,304 = 64 TB of storage.
The effect of extent size on the maximum volume and cluster size is shown in Table 1-12.
Table 1-12 Maximum volume and cluster capacity by extent size
Extent size (MB)
0016
0032
0064
0128
0256
0512
1024
2048
4096
8192
Use the same extent size for all storage pools in a clustered system. This rule is a
prerequisite if you want to migrate a volume between two storage pools. If the storage pool
extent sizes are not the same, you must use volume mirroring to copy volumes between
storage pools, as described in Chapter 4, "Storage pools" on page 143.
You can set a threshold warning for a storage pool that automatically issues a warning alert
when the used capacity of the storage pool exceeds the set limit.
(up to 1028 per system) is a collection of MDisks (up to 128) that are grouped
Maximum volume capacity for
normal volumes (GB)
002,048 (2 TB)
004,096 (4 TB)
008,192 (8 TB)
016,384 (16 TB)
032,768 (32 TB)
065,536 (64 TB)
131,072 (128 TB)
262,144 (256 TB)
262,144 (256 TB)
262,144 (256 TB)
Chapter 1. Overview of the IBM Storwize V5000 Gen2 system
Maximum storage capacity of
cluster
064 TB
128 TB
256 TB
512 TB
001 PB
002 PB
004 PB
0v8 PB
016 PB
032 PB
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