View figure.
The picture of the 3-frame system discussed in Chapter 5 is reproduced in Figure 48 below. Suppose you plan to have this system at some point in the future, and wish to partition it in the manner described in Example 3 - An SP with 3 frames, 2 SP Switches, and various node sizes:
Partition 1 - F1N01, F2N01, F1N05, F2N05,
F1N03, F2N07
Partition 2 - F1N09, F1N13, F2N13
F1N11, F2N11
Partition 3 - F3N01, F3N02, F3N05, F3N06,
F3N03, F3N07,
F3N09, F3N13
This layout is not one of those shipped by IBM, You would create it using the System Partitioning Aid. Further, if this system is not "in hand", then spsyspar cannot picture the system correctly, and shows only thin nodes.
Figure 48. Three frames with 2 switches
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Understand that the first frame in the figure really represents both of Frames 1 and 2: Frame 2 is an expansion frame for Frame 1 since it shares Frame 1's switch. Also, the nodes in the second frame pictured would be in Frame 3 of the real system, and would be numbered starting at 33, rather than 16. Once you complete this exercise, you will save a layout which you can use correctly once the real system is available. Partitioning is based on switch chips, not on node numbers.
Figure 49. Main window for Example 3 of Chapter 5
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Your objective for system partitions is to divide the system pictured in Figure 49 into 3 pieces: the lower half of Frame 1, the upper half of Frame 1, and Frame 2. You may perform the following tasks to accomplish this, and arrive at Figure 50:
Figure 50. System partitioning for Example 3 of Chapter 5
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To make the system represented look more like our system, you can use filtering on the Nodes pane. To do this, follow these steps:
The result is depicted in Figure 51. For the real system, Nodes 5, 25 and 29 will be high. Figure 51 looks good in this respect. However, Nodes 6 and 8 distort our perception of Node 5.
Figure 51. System partitioning for Example 3 of Chapter 5
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Validate and save the new layout by clicking on the fourth Tool Bar icon, "Generate files used to define system configuration." The resulting window appears in Figure 51. The code wants to store this new layout as an 8_8_16 configuration of a 2nsb0isb system, which is correct. (If you remove the filter you applied earlier, you indeed see partitions of 8, 8 and 16 nodes.) You can choose the directory extension, (the example uses directory extension "mine_1"). Therefore, the name of the directory containing the new layout is "layout.mine_1".
Figure 52. Dialog box for specifying name of new layout
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Click on "Generate" and receive the message in the following figure. Note the warning about losing the configuration. You should backup the layouts you create before reinstalling PSSP or ssp.top.
Figure 53. Message issued when new layout is saved
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Recall that the GUI (spsyspar) invokes the CLI (sysparaid) to validate and save a new layout. The previous GUI activity finished the job by issuing the command:
spsyspar -s mine_1 inputfile
where inputfile is as shown in Figure 54. (spsyspar chooses the correct global topology file based on the "Number of Switches ..." entries in this input file.)
Figure 54. CLI input file from spsyspar
+--------------------------------------------------------------------------------+ | | | Number of Nodes in System: 32 | | Number of Frames in System: 2 | | Frame Type: tall | | Switch Type: SP | | Number of Switches in Node Frames: 2 | | Number of Switches in Switch Only Frames: 0 | | Number of System Partitions: 3 | | Node Numbering Scheme: switch_port_number | | System Partition Name: Par1 | | Number of Nodes in System Partition: 8 | | 0-7 | | System Partition Name: Par2 | | Number of Nodes in System Partition: 8 | | 8 - 15 | | System Partition Name: Par3 | | Number of Nodes in System Partition: 16 | | 16 - 31 | +--------------------------------------------------------------------------------+
If you use the CLI directly, you can use an input file similar to that in Figure 54, but representing the facts more precisely:
Figure 55 is the appropriate input file.
Figure 55. Alternate CLI input file
+--------------------------------------------------------------------------------+ | | | Number of Nodes in System: 19 | | Number of Frames in System: 3 | | Frame Type: tall | | Switch Type: SP | | Number of Switches in Node Frames: 2 | | Number of Switches in Switch Only Frames: 0 | | Number of System Partitions: 3 | | Node Numbering Scheme: switch_port_number | | System Partition Name: Par1 | | Number of Nodes in System Partition: 6 | | 0-2 | | 4-6 | | System Partition Name: Par2 | | Number of Nodes in System Partition: 5 | | 8 | | 10-13 | | System Partition Name: Par3 | | Number of Nodes in System Partition: 8 | | 16 - 18 | | 20 - 22 | | 24 | | 28 | | | | | +--------------------------------------------------------------------------------+
When you save a new layout, supplemental files are saved in the respective directory. These include chip allocation files and performance files. For example, if you look at the layout.mine_1 directory saved earlier, the syspar.2.Par1 subdirectory contains the files spa.snapshot and spa.metrics.
The spa.snapshot file data is available for viewing in the GUI as the "Chip Allocation" page of the notebook for Par1. (First icon.) This GUI presentation is produced in Figure 56. Par1 is completely contained in Frames 1 and 2 and so only uses Switch 1, denoted NSB 1 (Node Switch Board 1) in the spa.snapshot file. The 2 chips on the left are the node-attached chips, and the 2 chips on the right provide connectivity between those chips. A rule which sysparaid adheres to is any 2 node chips in a partition must have 2 link switch chips through which to communicate. This guarantees minimal, acceptable bandwidth and reliability characteristics.
A summary of the chip assignments for all partitions is stored in an spa.snapshot file in the layout.mine_1 directory level.
Figure 56. Switch chips allocated to system partition Par1
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The spa.metrics data is available in the GUI on the "Performance" page of the notebook for Par1. This GUI presentation is given in Figure 57. Chips 5 and 6 are the node chips of Figure 56. The bandwidth numbers for Par1 are less than 100%. This measure is a comparison to the unpartitioned case where all 4 link switch chips would be available for the nodes on chips 5 and 6 to communicate through. So, in some cases, total traffic throughput between nodes of Par1 is cut by as much as half from the unpartitioned case. On average, that communication is only cut to 87.5%, since some of the nodes are on the same chip.
Figure 57. Performance numbers for system partition Par1
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