Mode
Category
Description
Default
MCU/RCU
1106
Dynamic
Provisioning
Dynamic
Tiering
This SOM is used to monitor the page usage rate of
parity groups
defined
to a pool, and perform
rebalance to balance the usage rate if the rate
differs
significantly
among parity groups.
Mode 1106 = ON:
The usage rate is checked once a
day and the rebalance works if the rate is not even.
Mode 1106 = OFF (default):
The rebalance does not
work even when the usage rate is not balanced.
The pool usage rate is determined as unbalanced
when there is 25% or more
difference
between the
usage rate of each parity group in the pool and the
average.
Note:
The term "page usage rate" refers to the
percentage of the number of assigned pages in each
PG compared to the total number of pages in the
pool. For HDT pools, the term "total number of
pages" is the number of pages assigned within each
specific
tier.
Examples:
1.
In an HDP pool, if the usage rates of PG1, PG2,
and PG3 are 50%, 40%, and 30% respectively, it
is not determined as unbalanced.
Because the average parity group usage rate is
(50%
+
40%
+
30%) / 3
=
40% and the
difference
in the rate between each parity group
and the average is 10% at the maximum.
2.
In an HDP pool, if the usage rates of PG1, PG2,
and PG3 are 80%, 40%, and 30% respectively, it
is determined as unbalanced.
Because the average parity group usage rate is
(80%
+
40%
+
30%) / 3
=
50% and the
difference
in the rate between each parity group
and the average is 30% at the maximum.
3.
In an HDT pool, if the usage rates of PG1, PG2,
and PG3 are 80% (SSD), 40% (SAS15K) and 30%
(SAS15K), it is not determined as unbalanced,
because:
■
The average parity group usage rate of Tier1
is (80%) / 1
=
80% and the
difference
in the
OFF
-
System option modes
Appendix B: System option modes
System Administrator Guide for VSP Gx00 models and VSP Fx00 models
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Summary of Contents for Virtual Storage Platform F400
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