IBM RELEASE 7.3, Management Manual

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Monitor free space from the top level storage class in each hierarchy to verify that the migration
and purge policy are maintaining adequate free space.
1.6.3. Performance Checklist
Measure data transfer rates in each COS for:
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Client writes to disk
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Migration from disk to tape
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Staging from tape to disk
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Client reads from disk
Transfer rates should be close to the speed of the underlying hardware. The actual hardware speeds can
be obtained from their specifications and by testing directly from the operating system (e.g., using dd to
read and write to each device). Keep in mind that transfer performance can be limited by factors external
to HPSS. For example, HPSS file read performance may be limited by the performance of the UNIX file
system writing the file rather than limits inside HPSS.
HPSS Management Guide November 2009
Release 7.3 (Revision 1.0) 20