Digital Equipment HSZ40, Справочное руководство

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SET mirrorset-name 2–63
HSZ40 Array Controller CLI Reference Manual
Select
BEST
_
FIT
to choose a replacement device from the spareset that most closely
matches the capacities of the remaining members. If more than one device in the spareset
is the correct size, the controller selects the device that gives the best performance.
Select
BEST
_
PERFORMANCE
to choose a replacement device from the spareset that results in
the best performance (the device should be on a different port than existing members). If
more than one device in the spareset has the best performance, the controller selects the
device that most closely matches the size of the remaining members.
NOPOLICY
retires a failing device from the mirrorset without selecting a replacement. This
causes the mirrorset to run with less than the nominal number of members until a
BEST
_
FIT
or
BEST
_
PERFORMANCE
policy is selected, or a member is manually replaced in the
mirrorset.
READ_SOURCE=ROUND_ROBIN
READ_SOURCE=LEAST_BUSY (Default)
READ_SOURCE=disk-name
The
READ
_
SOURCE
switch allows you to control which mirrorset member is used by the
controller to satisfy a read request.
Select
ROUND
_
ROBIN
to cause the controller to direct read requests to each
NORMAL
mirrorset member in sequential membership order. No preference is given to any
NORMAL
member.
Select
LEAST
_
BUSY
to cause the controller to direct read requests to the
NORMAL
mirrorset
member with the least busy work queue.
Select the disk-name of a specific member to cause the controller to direct all read requests
to that member. If that member fails out of the mirrorset, the controller reverts to the
LEAST
_
BUSY
method for mirrorset read requests.
COPY=NORMAL (Default)
COPY=FAST
__________________________ Note _____________________________
A normal mirrorset member is one whose entire contents are the same as all
other normal members.
____________________________________________________________
The
COPY
switch allows you to set the speed at which the controller copies data from
normal mirrorset members to new members.
Select
NORMAL
to prioritize other controller operations over the copy operation. The
controller uses relatively few resources to perform the copy, and there is little impact on
performance.