Veritas File System 5.0 Administrator's Guide (September 2006)
</DESTINATION>
</ON>
</CREATE>
The <BALANCE_SIZE> element with a value of one megabyte is specified for
allocations on tier2 volumes. For files allocated on tier2 volumes, the first
megabyte would be allocated on the first volume, the second on the second volume,
and so forth.
RELOCATE statement
The RELOCATE action statement of file placement policy rules specifies an action
that VxFS takes on designated files during periodic scans of the file system, and
the circumstances under which the actions should be taken. The fsppadm enforce
command is used to scan all or part of a file system for files that should be relocated
based on rules in the active placement policy at the time of the scan.
See the fsppadm(1M) manual page.
The fsppadm enforce scans file systems in path name order. For each file, VxFS
identifies the first applicable rule in the active placement policy, as determined
by the rules' SELECT statements. If the file resides on a volume specified in the
<FROM> clause of one of the rule's RELOCATE statements, and if the file meets the
criteria for relocation specified in the statement's <WHEN> clause, the file is
scheduled for relocation to a volume in the first placement class listed in the <TO>
clause that has space available for the file. The scan that results from issuing the
fsppadm enforce command runs to completion before any files are relocated.
The following XML snippet illustrates the general form of the RELOCATE statement:
<RELOCATE>
<FROM>
<SOURCE>
<CLASS>...placement_class_name...</CLASS>
</SOURCE>
<SOURCE>...additional placement class specifications...
</SOURCE>
</FROM>
<TO>
<DESTINATION>
<CLASS>...placement_class_name...</CLASS>
<BALANCE_SIZE Units="units_specifier">
...chunk_size...
</BALANCE_SIZE>
</DESTINATION>
Dynamic Storage Tiering
File placement policy rules
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