Admin Alert: Getting Started with Trial Capacity on Demand, Part 2

December 12, 2007 Joe Hertvik

In Part 1 of this article, Getting Started with Trial Capacity on Demand, Part 1, I described how I recently approached the decision to activate additional trial processors on a client’s System i 550 box. This week I’m completing the process by reviewing the activation process steps and the various published and unpublished steps you need to take to add temporary processing power to your system.

The Basic Situation

Capacity on Demand (CoD) is IBM‘s way of delivering (and selling) additional processors that can be activated in a very short time when your system is experiencing performance issues. Many later model System i servers (including models 550, 570, and 595) are shipped with the maximum number of processors available on the system. The trick is that only the processors that you ordered are activated. When you need additional power, you can activate the additional processors on a permanent, temporary, or trial basis. For more information about IBM’s different types of processor activation, see last week’s article.

In my situation, I was working on a System i 550 box that was experiencing performance issues while completing nightly batch processing. These issues were going to be exacerbated as the company headed into the big holiday season, when nightly traffic could easily double. After analyzing system performance, we discovered that our two system processors (out of a possible four) were overloaded and starting to bottleneck the system. To test the effect of adding extra processors before committing to permanent processor activation, we decided to temporarily activate an additional processor on the system under IBM’s Trial CoD program, which allows a company to activate additional processors on a System i box for an entire month without cost. Once you pass the month deadline, however, IBM will start billing you for using any extra processors that you activated.

I found that activating additional System i processors is a fairly easy process. It consists of the following four steps:

Applying for and receiving a processor activation code
Preparing your partitions to use additional processors
Applying the processor code to your system
Deactivating the code when you’re finished

Here’s an overview of how it worked in my case.

Step 1: Applying For and Receiving a Processor Activation Code

Additional processor CoD is activated by entering an IBM supplied CoD code into the Manage On Demand Activations area of your Hardware Management Console (HMC). You can get the code in one of two ways. It can be downloaded from IBM’s Trial CoD Website or it can be ordered through your business partner. In order to retrieve a downloaded code, you need to produce a number of pieces of vital product data for your System i box. This information includes system type, System Serial Number, anchor card information, resource identifier, activated resources, sequence number, and entry check. Don’t worry if you don’t know where these items are. There’s a link on the CoD site that provides instructions for retrieving this information. In addition to retrieving your system’s product data, you will also be required to fill out information about your company and agree to IBM’s terms for downloading.

If you go through your business partner or IBM to get the code, you still have to provide much of the same information and you may also have to sign a contract. Of course, the other difference between downloading and going through a business partner is that you get the code immediately with the download function so I would recommend downloading over ordering.

Step 2: Preparing Your Partitions To Use Additional Processors

Now that you have the activation code, you will probably want to immediately activate the extra processors on your machine. Don’t. You may accidentally wind up wasting processor time off your 30-day trial. Before you fire up any new processors, you have to make sure that any target partition that you want to add processors to can accept another processor. Each partition profile has a maximum processing units parameter that controls how many total processors can be assigned to that partition. If your partition’s maximum processing units parameter is less than the total number of processors that you want to assign to that partition, you’ll have to change the parameter and reactivate (IPL) the partition to use the new value.

The reason I say that you should wait until your partition is ready to accept the new processor(s) is that most System i shops just can’t re-IPL their systems anytime of the day or night. Since these systems are constantly in use, IPLs have to be scheduled in advance and you may not be able to IPL your target partition to change your maximum processor setting for several days. If you activate your 30-day trial processors and you need several days to IPL your box to change the maximum processing units parameter, you’ll be wasting trial CoD time until the IPL is completed because the new value won’t be available until after an IPL. So you need to check and change (if necessary) your partition’s maximum processing units parameter and IPL the box before you can use the new processor.

To check the maximum processing units parameter for your partition, open the Server and Partition→Server Management→server name for your machine→Partitions path on your HMC. Right-click on the partition profile where you are planning on adding a processor and select the properties option from the pop-up menu that appears. On the logical partition profile properties screen, select the processors tab. On this screen, you’ll see two areas called processing units and virtual processors, both of which are directly tied to how many processors can be assigned to each partition.

The processing units describes the maximum, minimum, and desired number of processing units that are defined for this partition. In i5/OS you can assign fractional processors to a partition in units as low as .05 processor (i.e., rather than assigning one processor to a partition, you could assign .25 processor or 1.25 processor or any fractional number up to the maximum available number of processors). The minimum processing units field on this screen defines the minimum number of processor units that need to be assigned to the partition in order for the partition to IPL. If the partition is unable to obtain this number of units, the partition will not be activated.

The desired processing units field is the number of processors that you want the partition to have when it starts up. If the partition cannot get the desired number of processor units but it can still get the minimum number of processing units, it will start with the minimum. However, the number that we’re really interested in is the maximum processing units.

Maximum processing units defines the highest number of processing units that can be assigned to this partition when you dynamically move or assign processor units to it. If because of the Trial CoD, you plan to add enough processor capability so that the total number of processors on the partition would exceed the number in the maximum processing units field, you will need to change the maximum processing units field to be greater than or equal to the total number of processing units that the partition will have after the addition. If you don’t, the HMC will not let you add processor capacity to this partition above the value in maximum processing units. If the value in the maximum processing units parameter is greater than or equal to the total number of processing units you are planning to assign to the system, you won’t need to change this field.

If you are using virtual processors on your partitions, you may also need to change the maximum processing units parameter in the virtual processors area of the screen. This will allow your partition to take advantage of the new trial processors when assigning virtual processors.

If you’ve changed either the maximum virtual processors field or the maximum processing units field on the screen, click OK to save your changes. However, you haven’t yet finished increasing the maximum number of processors that your partition can contain. In order to apply the new processor values for the partition, you have to completely shut down the partition and reactivate it with the new partition properties values that you just changed. To do that, perform the following two functions.

First, completely shut down your partition by using the following power down system command on the system console (PWRDWNSYS).

PWRDWNSYS OPTION(*IMMED) RESTART(*NO)

This command will take down the system without restarting it, which is necessary for changing your processing unit parameters.

Second, once the partition is powered down, go back to the HMC to activate the partition with its new values. To activate your processor change, right-click on the partition profile and select activate from the pop-up menu that appears. This will restart your system. Don’t take any other option to start the system. Once the partition is IPLed through the activate function, all the changes you made to maximum processing units or maximum virtual processors fields will now be in effect for the partition.

Repeat this routine for any other partition that you want to assign new trial CoD processors to. Once you’re finished with this configuration, you are now ready to add the trial CoD processors to your partitions.

Step 3: Applying the Processor Code to Your System

Applying the code is the easiest part of the process. You simply go to your HMC and open up the Server and Partition→Server Management node. In the display’s right-hand pane, right-click on the System i server name that you will be activating the processor(s) for. Select Manage On Demand Activations→Capacity on Demand→Enter CoD Code from the pop-up menu that appears. Type or paste the activation code that you received from IBM into the code field and then click on OK. A confirmation window may appear. If it does, click yes to confirm the activation.

At this point, your trial processor(s) is available to be used by any uncapped or capped logical partitions on your system. An uncapped partition can use as many processors from the shared processor pool as are defined in the partition’s maximum virtual processors parameters. A capped logical partition can use as many processors as are assigned in its maximum processing units parameter. If you want to increase the number of processors that are assigned to a partition, follow the instructions in the managing processor resources dynamically using version 6 or earlier of the HMC entry in the IBM System Hardware Information Center. If you want a more detailed description of what capped and uncapped partition do for a partition, see IBM’s System Hardware Information Center Web page on the topic.

Step 4: Deactivating the Code When You’re Finished

During the time that you are running the trial CoD processors, on the partitions where you added trial CPUs, you will see occasional CPF9E7A messages in the QSYSOPR message queue that read:

Operating System/400 usage limit exceeded - operator action required.

These messages are reminders that the additional processors are only temporary and that they will expire soon. To see how many days you have left in your trial period, open the Server and Partition→Server Management node on the HMC and right-click on the System i Server Name and select Manage On Demand Activations→Capacity on Demand→Processors→Capacity Settings. On the capacity settings screen that appears, click on the Trial CoD tab and you will see the state of your Trial CoD activation (running or non-running), the number of activated Trial CoD processors, and the number of days and hours remaining in your trial period. If you are not planning on permanently activating these processors, keep close watch on the number of days left because IBM will check the reporting on your activation and charge you for any days that you used beyond the trial period.

When the trial period is about to expire and you’re ready to deactivate the trial processors, you can once again go into the HMC and right-click on the System i server name and select Manage On Demand Activations→Capacity on Demand→Processors→Stop Trial CoD. This option will allow you to end your trial CoD without being charged extra by IBM. If you decide to purchase the extra processors, work with your business partner or IBM to get and apply the permanent processor activation codes.