SuperDome Repartitioning

[David Child_1]

I have a 32 way Superdome and it is currently split into 4 nPars as follows:

Partition 0 = Cells: 0 & 2 (0 is core)
Partition 1 = Cells: 1 & 3 (1 is core)
Partition 2 = Cells: 4 & 6 (4 is core)
Partition 3 = Cells: 5

There is 1 cell board that had not been assigned to a partition until we determined which part of the application and/or database would need the extra horse-power. We have determined that partition 0 will require the extra resources. The problem is that according to the Partitions guide the supported configuration needs to look like:

Partition 0 = Cells: 0, 1 & 2 (0 is core)
Partition 1 = Cells: 5 & 7
Partition 2 = Cells: 4 & 6
Partition 3 = Cells: 3

Its no problem moving the drives, etc. around to get this configuration, but there is a problem with the fact that currently cell #1 is attached to a core I/O and cell #3 is not. I know there is some internal cabling that needs to be moved, but I don't know what else needs to be done. I couldn't find this in any manuals.

Our environment is very dynamic and I know that management would not be happy if we have to call HP Services out every time we need to reconfigure one of our superdomes.

At this point my options appear to be:

1. Get HP Services to come out and rework the cabinet
2. Find a manual or some instructions on how to rewire the core I/O <-> Cell.
3. Just add cell #7 into partition 0 as it is. I don't know what kind of performance hit this would be (if any), but I know it is not a supported configuration.

Any suggestions would be greatly appreciated.

Thanks,
David

[David Child_1]

I have come up with one other option. It is a variation of #3:

4.
Partition 0 = Cells: 0 & 2 & 3
Partition 1 = Cells: 1
Partition 2 = Cells: 4 & 6
Partition 3 = Cells: 5 & 7

This way partitions 1, 2, and 3 are supported configurations. Partition 0 will not be, but at least all four cells are in the same quad and shouldn't run into the performance issue with adding cell 7 into an nPar with cells 0 and 2.

Any thoughts?

David

[Oleg Khoroshylov]

Hi David,

I think that there is no need for moving internal cabling inside Superdome. Configuration Guide for Superdome tells that "resources may be removed from one partition and added to another without having to physically manipulate the hardware just by using commands that are part of the System Management interface".


BR,
OK

[David Child_1]

Thanks Oleg,

Yes, technically you can reassign resources as required, but HP only supports a limited number of configurations. As I listed above, I cannot put together the 4 nPar configurations I want in an HP supported way without recabling.

I reworked the system this weekend and went with my last suggestion:

Partition 0 = Cells: 0 & 2 & 3
Partition 1 = Cells: 1
Partition 2 = Cells: 4 & 6
Partition 3 = Cells: 5 & 7

Partitions 1, 2, and 3 are in supported configurations. Partition 0 will not be, but I kept all three cells in the same quad for performance.

For future reference: if you are setting up a 32way superdome with several 2 cell nPars, make sure you design it so cell 0 and cell 3 are attached to core I/O as are cells 4 and 7. This way you can have supported 2 cell nPars AND you can easily make a 3 cell nPar in a supported configuration. This applies to 16 say superdomes as well.