Fujitsu Siemens Computers CentricStor V3.1D, Руководство пользователя

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U41117-J-Z125-7-76
Reorganization Selected system administrator activities
When the percentage of valid data on a physical volume which is in
write
status and is
not currently mounted in a Physical Device Service is below this limit value and at the
same time a reorganization is in progress because a scratch tape limit value has been
fallen below, this physical volume is placed in
read
status, and it is therefore a candidate
for reorganization.
Default:
70
Parallel Request Number
When a PV is reorganized, a movement request for each logical volume of this physical
volume is sent to the VLM. The parameter defines the number of such movement
requests which can be processed in parallel.
The value specified may not be too high for the following reasons:
–
Space must be created in the TVC for each logical volume which is to be read in,
i.e. under certain circumstances other logical volumes are displaced unnecessarily.
– The VLM limits the number of logical volumes for reorganization per cache. When
this value is reached, subsequent “Move” requests must wait.
Default: 5
Move Cancel Time
The PLM monitors the progress of the reorganization of a physical volume. This value,
specified in seconds, is used for this purpose.
If the status of the reorganization of a physical volume remains unchanged for this pe-
riod, the reorganization of this physical volume is aborted and, if applicable, the next vo-
lume is reorganized.
The timer is reset for each of the individual steps listed in the
section “When is a reor-
ganization performed?” on page 75 .
Default: 1800
Write Throughput
This parameter specifies the estimated write performance, in MiB/s, for reorganization
of a physical volume. It plays a part in determining the physical volume for which the
shortest reorganization time is to be expected (see
section “Which physical volume is
selected for reorganization?” on page 76 ).
Default: 5
Write Overhead
This parameter specifies the estimated overhead, in seconds, for each logical volume
which is to be written. It plays a part in determining the physical volume for which the
shortest reorganization time is to be expected (see
section “Which physical volume is
selected for reorganization?” on page 76 ).
Default: 3