Veritas™ File System 5.0.1 Administrator's Guide

period are to be relocated to tier1 volumes. Bytes written to the file during the
period of interest are not part of this calculation.
Using I/O temperature rather than a binary indicator of activity as a criterion for
file relocation gives administrators a granular level of control over automated
file relocation that can be used to attune policies to application requirements. For
example, specifying a large value in the <PERIOD> element of an upward relocation
statement prevents files from being relocated unless I/O activity against them is
sustained. Alternatively, specifying a high temperature and a short period tends
to relocate files based on short-term intensity of I/O activity against them.
I/O temperature and access temperature utilize the sqlite3 database for building
a temporary table indexed on an inode. This temporary table is used to filter files
based on I/O temperature and access temperature. The temporary table is stored
in the database file .__fsppadm_fcliotemp.db, which resides in the lost+found
directory of the mount point.
Multiple criteria in file placement policy rule
statements
In certain cases, file placement policy rule statements may contain multiple clauses
that affect their behavior. In general, when a rule statement contains multiple
clauses of a given type, all clauses must be satisfied in order for the statement to
be effective. There are four cases of note in which multiple clauses may be used.
Multiple file selection criteria in SELECT statement clauses
Within a single SELECT statement, all the selection criteria clauses of a single type
are treated as a selection list. A file need only satisfy a single criterion of a given
type to be designated.
In the following example, files in any of the db/datafiles, db/indexes, and
db/logs directories, all relative to the file system mount point, would be selected:
<SELECT>
<DIRECTORY Flags="nonrecursive">db/datafiles</DIRECTORY>
<DIRECTORY Flags="nonrecursive">db/indexes</DIRECTORY>
<DIRECTORY Flags="nonrecursive">db/logs</DIRECTORY>
</SELECT>
This example is in direct contrast to the treatment of selection criteria clauses of
different types. When a SELECT statement includes multiple types of file selection
criteria, a file must satisfy one criterion of each type in order for the rule's action
statements to apply.
173Dynamic Storage Tiering
Multiple criteria in file placement policy rule statements