Veritas™ File System 5.0.1 Administrator's Guide

Indicates the placement classes to which qualifying files should be
relocated. Unlike the source placement class list in a FROM clause,
placement classes in a <TO> clause are specified in priority order.
Files are relocated to volumes in the first specified placement class if
possible, to the second if not, and so forth.
The <TO> clause of the RELOCATE statement contains a list of
<DESTINATION> XML elements specifying placement classes to whose
volumes VxFS relocates qualifying files. Placement classes are
specified in priority order. VxFS relocates qualifying files to volumes
in the first placement class specified as long as space is available. A
<DESTINATION> element may contain an optional <BALANCE_SIZE>
modifier sub-element. The <BALANCE_SIZE>modifier indicates that
relocated files should be distributed across the volumes of the
destination placement class in chunks of the indicated size. For
example, if a balance size of one megabyte is specified for a placement
class containing three volumes, VxFS relocates the first megabyte the
file to the first (lowest indexed) volume in the class, the second
megabyte to the second volume, the third megabyte to the third
volume, the fourth megabyte to the first volume, and so forth. Using
the Units attribute in the <BALANCE_SIZE> XML tag, the chunk value
may be specified in the balance size value may be specified in bytes
(Units="bytes"), kilobytes (Units="KB"), megabytes (Units="MB"),
or gigabytes (Units="GB").
The <BALANCE_SIZE> element distributes the allocation of database
files across the volumes in a placement class. In principle, distributing
the data in each file across multiple volumes distributes the I/O load
across the volumes as well.
<TO>
An optional clause that indicates the conditions under which files to
which the rule applies should be relocated. Files that have been
unaccessed or unmodified for a specified period, reached a certain
size, or reached a specific I/O temperature or access temperature level
may be relocated. If a RELOCATE statement does not contain a <WHEN>
clause, files to which the rule applies are relocated unconditionally.
A <WHEN> clause may be included in a RELOCATE statement to specify
that files should be relocated only if any or all of four types of criteria
are met. Files can be specified for relocation if they satisfy one or more
criteria.
<WHEN>
The following are the criteria that can be specified for the <WHEN> clause:
This criterion is met when files are inactive for a designated period
or during a designated period relative to the time at which the
fsppadm enforce command was issued.
<ACCAGE>
Dynamic Storage Tiering
File placement policy rules
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