Sun Microsystems StorEdge 6920 System, Getting Started Manual

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Chapter 3 Configuring the System 61
In a concatenated volume, virtual disk partitions are filled with data sequentially,
with the second disk being written to when no space remains on the first, the third
when no room remains on the second, and so on. The system distributes the volume
space across devices by using the devices with the smallest amount of available
space first.
In a striped volume, the system divides data into blocks and distributes (or stripes)
the data blocks evenly across several disk blocks. The system distributes the volume
space across devices equally by using the smallest number of devices possible to
make a volume of the desired size. Striping distributes (reads and writes) data to
two or more slices that reside on different disks.
A concatenated volume does not have the enhanced performance of a striped
volume. In a concatenated volume the system writes a single block to a single virtual
disk. In a striped volume, each block is divided, and portions of the data are written
to different disks simultaneously. Striping data improves your disk performance
because it performs simultaneous disk read/write operations on multiple disks.
You can choose any of the following options:
■
Use the default storage profile with the existing default configuration (as is)
■
Select one of the predefined storage profiles shipped with the system
■
Create a custom storage profile
For more information about virtualization strategies, go to the online help system by
clicking the Help button. Click the Search tab and type
concatenated
or
striped.
What Is a Volume?
Volumes are “containers” into which applications, databases, and file systems can
put data. A volume can be a physical disk or a virtual disk mapped from one or
more extents. (An extent is a set of disk blocks with logical consecutive addresses.)
The default storage configuration defines one domain with a single storage pool that
uses a default profile. To use your storage efficiently, you must create volumes from
a storage pool that is associated with a storage profile.
For more information about volumes, go to the online help system by clicking the
Help button. Click the Search tab and type
volumes.
What Is a Storage Pool?
Storage pools are collections of virtual disks with the same configuration and
performance characteristics. A storage pool can contain zero, one, or more virtual
disks. You manage the system’s virtual disks as a pool of storage space. By using