The iCOD software tracks the expected number of inactive (iCOD) components
(processors, cells, and memory) in a complex and knows the actual
number of active and inactive components. The complex is in compliance
if the actual number of inactive components meets or exceeds the
expected number of inactive components.
The complex is out of compliance if the actual number of inactive components
is less than the expected number of inactive components and no temporary
capacity exists.
However, a complex can also get out of compliance if a cell
is removed from the complex. For example, if a cell contains inactive
processors that are contributing to compliance, and the cell is
removed, it is possible that the complex is out of compliance and
TiCOD begins to be debited.
Example A-1 Removing
a Cell and Decreasing the Actual Number of Inactive Processors
For example, a complex contains two cells, with two partitions
having two iCOD and two active processors each. The iCOD software
expects the complex to have four inactive processors. If one of
the cells (0) experiences a hardware problem, and you remove the
cell, the complex is left with only one cell that contains two active
and two inactive processors. The complex is now out of compliance
because four inactive processors are expected to be in the complex,
yet there are only two inactive processors.
Table A-1 Removing a Cell — Decrease Inactive Processors
State | Partition (Cell) 0 | Partition (Cell) 1 | Notes |
|---|
Before Cell 0 is Removed | 2 active
2 inactive | 2 active
2 inactive | 4 inactive processors and 4 iCOD processors
expected (in compliance) |
After Cell 0 is Removed | 0 active
0 iCOD | 2 active,
2 inactive | 2 inactive processors and 4 iCOD processors
expected (out of compliance) |
In the above example, because the removed cell causes the
complex to be out of compliance, TiCOD begins to be debited at the
rate of two processor-hours per hour.
TiCOD allows for increased capacity, even in the presence
of a cell hardware failure, which necessitates the removal and repair
of a cell. Removal of a cell, followed by a reboot of the partition
it was assigned to, results in a maximal number of active processors
in the partition (subject to the configured intended number of active
processors), while the maximum number of iCOD processors are relegated
to the removed cell. During the period when the cell is absent,
TiCOD is consumed for each (newly missing) iCOD processor that was
shifted to the removed cell. Having additional iCOD capacity and
TiCOD allows for increased capacity during rare hardware failures
that would otherwise not have been possible.
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