Hitachi Virtual Storage Platform, Руководство пользователя и справочник

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Functional and Operational Characteristics
2–29
Hitachi VSP User and Reference Guide
704 Open and
Mainframe To reduce the chance of MIH, this option can reduce
the priority of SI, VM, CoW Snapshot, Flash Copy or
Resync copy internal IO requests so that host IO
has a higher priority. This mode creates new work
queues where these jobs can be assigned with a
lower priority.
Mode 704 = ON:
Copy processing requested is registered into a
newly created queue so that the processing is
scheduled with lower priority than host I/O.
Mode 704 = OFF: (Default)
Copy processing requested is not registered into a
newly created queue. Only the existing queue is
used.
Note:
If the PDEV is highly loaded, the priority of Read/
Write processing made by SI, VM, Snapshot,
Compatible FlashCopy® V2 or Resync may become
lower. As a consequence the copy speed may be
slower.
OFF .
720 Universal
Volume
Manager
(Mainframe
and Open) Supports the Active Path Load Balancing (APLB)
mode.
Mode 720 = ON:
The alternate path of EVA (A/A) is used in the APLB
mode.
Mode 720 = OFF (default):
The alternate path of EVA (A/A) is used in the Single
mode.
Note:
Though online setting is available, the setting will
not be enabled until Check Paths is performed for
the mapped external device.
OFF .
Mode Category Description Default MCU/RCU