Superdome IO cage <-> cell connection

[Michal Gorski]

Hi

I've got some question about Integity SD architecture.

Lets assume that I have ordered 8-cell SD with 4 PCI shelves.

1. What would be default scheme of cell <-> IO connections ?
Cell numbers: 0/0 – 0/7
IO: 0/0/1 – 0/0/3 - front
0/1/1 - 0/1/3 –rear

2. What are possible modifications of this assignment ?

Second scenario: 2-cell SD with 2 PCI shelves.

1. What cell and IO slots would be occupied in the scenario ?
2. How shelves – cell assignment would look like ?



Thanks in advance for help.

Michal

[Udo Werner]

Hello Michal,

normaly each Superdome is configured in a Integration Center according to customer needs.

So where is no default configuration as far as I know, but everything is posssible. You can connect each PCI Chassis to each cell. Of course this needs physical move of cables, but which IO chassis will be on which cell is up to you. This is the same for a 2 cell SD.

Best regards,
Udo

[Torsten.]

According to Udo's information, there is no default.

To get the current connections, run

MP:CM> io

or from the OS

# parstatus



Example for the MP command:


MP:CM> io

--------------------------+
Cabinet | 0 | 1 |
--------+--------+--------+
Slot |01234567|01234567|
--------+--------+--------+
Cell |XXXXXXXX|XXXXXXXX|
IO Cab |0.......|1.......|
IO Bay |1.......|1.......|
IO Chas |3.......|3.......|

[Torsten.]

again, hope its better now:

MP:CM> io

--------------------------+
Cabinet_|___0____|___1____|
--------+--------+--------+
Slot____|01234567|01234567|
--------+--------+--------+
Cell____|XXXXXXXX|XXXXXXXX|
IO Cab__|0.......|1.......|
IO Bay__|1.......|1.......|
IO Chas_|3.......|3.......|

[Torsten.]

no way, find it attached.

[Michal Gorski]

Thank you for your help.

[Mridul Shrivastava]

I do agree with Torsten and Udo, however while going through charles Keened book I came across nifty-54 diagram and it says that the idea here is to produce a configuration that offers both High Availability and High Performance.

It also mentions that By default, certain cells are connected to certain IO cardcages. By default cell 0 is connected to an IO cardcage located in the rear left of the main cabinet (looking from the front of the cabinet), while cell 6 is connected to the IO cardcage front right of the cabinet. It may be that your system complex has been cabled differently from this default.

I am just pasting few more lines here about the guidelines.High Availability and High Performance criteria can be summarized as follows:

Configure your largest partitions first.

Configure the same number of CPUs per cell.

Configure the same amount of memory per cell.

Configure a power of 2 GB of memory to aid memory interleaving.

Configure the number of cells per partition as a power of 2. An odd number of cells will mean that a portion of memory is interleaved over a subset of cells.

Choose cells connected to the same XBC.

Configure at least two CPUs per cell.

Configure at least two Echelons/Rank of memory per cell.

Use two IO cardcages per partition.

Install a Core IO card in each IO cardcage.

Use even and then odd numbered cells.

A maximum of 64 processors per partitions, e.g., 32 dual-core processors = 64 processors in total.

If we marry this information back to our discussion on the default wiring of cells to IO cardcages, we start to appreciate why the default wiring has been set up in the way it has. We also start to realize the necessity of understanding how the complex has been configured in order to meet both goals of High Availability and High Performance. In the simple 2-cell example that we discussed earlier, it now becomes apparent that the optimum choice of cells would either be 0 and 2 or 4 and 6:

Both cells are located on the same XBC minimizing latency across separate XBC interfaces.

Both cells are already wired to a separate IO cardcages on separate IO backplanes.

Inter-cell communication is optimized between even or odd cells.

[Mridul Shrivastava]

It looks like that you are new to ITRC forums. A warm welcome to the community and
don't forget to assign points if your queries has been answered ;)

Enjoy and Have a nice day.

Mridul