Veritas Storage Foundation™ for Oracle 5.0.1 Administrator's Guide

file system over multiple volumes, each volume with properties of its own. This
helps administrators specify which data goes on which volume types. For more
details about MVS, see Veritas Volume Manager Administrator's Guide. Setting
up a storage configuration for MVS operations is a system administrator's
responsibility and requires superuser (root) privileges.
Note: Veritas Storage Foundation for Oracle RAC does not support storage
checkpoint allocation policies.
Multi-Volume File Systems provide a database administrator, through the
checkpoint administration interface, the ability to create Storage Checkpoint
Allocation Policies.
A Storage Checkpoint Allocation policy specifies a list of volumes and the order
in which to attempt allocations. Once defined, a database administrator can use
these policies to:
■ Control where the storage checkpoint should be created, enabling separation
of metadata and data of a storage checkpoint to different volumes.
■ Separate storage checkpoints so that data allocated to a storage checkpoint is
isolated from the primary file system. This helps control the space used by
the checkpoint and prevents the checkpoint from fragmenting the space in
the primary fileset.
When policies are assigned to a storage checkpoint, the database administrator
must specify the mapping to both metadata and file data. If no policies are specified
for the storage checkpoint, the data is placed randomly within the primary file
system. Data and metadata of storage checkpoints can have different policies
assigned to them or use the same policy to be applied to data and metadata.
Multiple checkpoints can be assigned the same checkpoint allocation policy. A
partial policy is also allowed; a partial policy means that the policy does not exist
on all file systems used by the database.
Once the policy is assigned to checkpoints, the allocation mechanism attempts
to satisfy the request from each device in the policy in the order the devices are
defined. If the request cannot be satisfied from any of the devices in the policy,
the request will fail, even if other devices exist in the file system which have space.
Only those devices can provide allocation that are listed in the policy. This
implementation is the mechanism for preventing allocation requests from using
space in other devices which are not specified in the policy. It is recommended
that you allocate sufficient space for the volumes defined in the Storage Checkpoint
policy or update the policy to include additional volumes. This also helps in
retaining the old Storage Checkpoints.
Using Storage Checkpoints and Storage Rollback
Storage Checkpoint allocation policies
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