Veritas Storage Foundation 5.1 SP1 Advanced Features Administrator"s Guide (5900-1503, April 2011)
</WHEN>
</RELOCATE>
<DELETE>
<WHEN>
<ACCAGE Units="days">
<MIN Flags="gt">90</MIN>
</ACCAGE>
</WHEN>
</DELETE>
As written with the RELOCATE statement preceding the DELETE statement, files
will never be deleted, because the <WHEN> clause in the RELOCATE statement applies
to all selected files that have not been accessed for at least 30 days. This includes
those that have not been accessed for 90 days. VxFS ceases to process a file against
a placement policy when it identifies a statement that applies to that file, so the
DELETE statement would never occur. This example illustrates the general point
that RELOCATE and DELETE statements that specify less inclusive criteria should
precede statements that specify more inclusive criteria in a file placement policy
document. The GUI automatically produce the correct statement order for the
policies it creates.
File placement policies and extending files
In a VxFS file system with an active file placement policy, the placement class on
whose volume a file resides is part of its metadata, and is attached when it is
created and updated when it is relocated. When an application extends a file, VxFS
allocates the incremental space on the volume occupied by the file if possible. If
not possible, VxFS allocates the space on another volume in the same placement
class. For example, if a file is created on a tier1 volume and later relocated to a
tier2 volume, extensions to the file that occur before the relocation have space
allocated on a tier1 volume, while those occurring after to the relocation have
their space allocated on tier2 volumes. When a file is relocated, all of its allocated
space, including the space acquired by extension, is relocated to tier2 volumes
in this case.
Using SmartTier with solid state disks
The SmartTier feature has been enhanced with the following placement policy
features to support SSD-based tiers:
■ Allowance of fine grained temperatures, such as allowing hours as units for
the <IOTEMP> and <ACCESSTEMP> criteria
Administering SmartTier
File placement policies and extending files
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