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Using the GCU Charts  



The GCU contains a considerable amount of configuration data and can grow quite large for complex Galaxy configurations. If the GCU displayed all the information it has about the system, the display would become unreasonably complex. To avoid this problem, the GCU provides Galaxy charts. Charts are a set of masks that control the visibility of the various components, devices, and interconnections. The entire component hierarchy is present, but only the components specified by the selected chart are visible. Selecting a different chart alters the visibility of component subsets.

By default, the GCU provides five preconfigured charts:

Each chart is designed to show a specific component relationship. Some GCU command operations can be performed only within specific charts. For example, you cannot reassign CPUs from within the Physical Structure chart. The Physical Structure chart does not show the Galaxy instance components; you would have no target to drag and drop a CPU on. Similarly, you cannot perform a hot-swap inquiry operation if you are displaying the Logical Structure chart. Device hot-swapping is a physical task that cannot be represented in the logical chart. Because you can modify the charts, the GCU does not restrict its menus and command operations to specific chart selections. In some cases, the GCU displays an informational message to help you select an appropriate chart.

Component Identification and Display Properties  

Each component has a unique identifier. This identifier can be a simple sequential number, such as with CPU IDs, a physical backplane slot number, as with I/O adapters, or a physical address, as with memory devices. Each component type is also assigned a shape and color by the GCU. Where possible, the GCU further distinguishes each component using supplementary information it gathers from the running system.

The display properties of each component are assigned within the Galaxy Configuration Ruleset (SYS$MANAGER:GALAXY.GCR). Do not edit this file, except to customize certain display properties, such as window color or display text style.

You can also customize the text that gets displayed about each component. Each component type has a set of statements in the ruleset that determine its appearance, data content, and interaction.

One useful feature is the ability to select which text is displayed in each component type on the screen. The device declaration in the ruleset allows you to specify the text and parameters, which make up the display text statement. A subset of this display text is displayed whenever the zoom scale factor does not allow the full text to be displayed. This subset is known as the mnemonic. The mnemonic can be altered to include any text and parameters.

Physical Structure Chart  

The Physical Structure chart describes the physical hardware in the system. The large rectangular component at the top, or root, of the chart represents the physical system cabinet itself. Typically, below the root, you find physical components such as modules, slots, arrays, adapters, and so on. The type of components presented and the depth of the component hierarchy is directly dependent on the level of support provided by the console firmware for each hardware platform. If you are viewing a single-instance Galaxy on any Alpha system, then only a small subset of components can be displayed.

As a general rule, the console firmware presents components only down to the level of configurable devices, typically to the first-level I/O adapter or slightly beyond. It is not a goal of the GCU or of the Galaxy console firmware to map every device, but rather those that are of interest to Galaxy configuration management.

The Physical Structure chart is useful for viewing the entire collection of components in the system; however, it does not display any logical partitioning of the components.

In the Physical Structure chart you can:

Hardware Root  

The topmost component in the Physical Structure chart is known as the hardware root (HW_Root). Every Galaxy system has a single hardware root. It is useful to think of this as the physical floorplan of the machine. If a physical device has no specific lower place in the component hierarchy, it appears as a child of the hardware root. A component that is a child can be assigned to other devices in the hierarchy when the machine is partitioned or logically defined.


NoteClicking the root instance of any chart performs an auto-layout operation if the Auto Layout mode is set.

Ownership Overlay  

Choose Ownership Overlay from the Windows menu to display the initial owner relationships for the various components. These relationships indicate the instance that owns the component after a power cycle. Once a system has been booted, migratable components may change owners dynamically. To alter the initial ownership, the console environment variables must be changed.

The ownership overlay has no effect on the Physical Structure chart or the Failover Target chart.

Logical Structure Chart  

The Logical Structure chart displays Galaxy communities and instances and is the best illustration of the relationships that form the Galaxy. Below these components are the various devices they currently own. Ownership is an important distinction between the Logical Structure chart and Physical Structure chart. In a Galaxy, resources that can be partitioned or dynamically reconfigured have two distinct owners.

The owner describes where the device turns up after a system power-up. This value is determined by the console firmware during bus-probing procedures and through interpretation of the Galaxy environment variables. The owner values are stored in console nonvolatile memory so that they can be restored after a power cycle.

The CURRENT_OWNER describes the owner of a device at a particular moment in time. For example, a CPU is free to reassign among instances. As it does, its CURRENT_OWNER value is modified, but its owner value remains whatever it was set to by the LP_CPU_MASK# environment variables.

The Logical Structure chart illustrates the CURRENT_OWNER relationships. To view the nonvolatile owner relationships, select Ownership Overlay from the Window menu.

The following sections describe the components of the Logical Structure chart.

Software Root  

The topmost component in the Logical Structure chart is known as the software root (SW_Root). Every Galaxy system has a single software root. If a physical device has no specific owner, it appears as a child of the software root. A component that has a child can be assigned to other devices in the hierarchy when the machine is logically defined.


NoteClicking the root instance of any chart performs an auto-layout operation if the Auto Layout mode is set.

Unassigned Resources  

You can configure Galaxy partitions without assigning all devices to a partition, or you can define but not initialize one or more partitions. In either case, some hardware may be unassigned when the system boots.

The console firmware handles unassigned resources in the following manner:

Devices that remain unassigned after the system boots appear to be assigned to the software root component and may not be accessible.

Community Resources  

Resources such as shared memory can be accessed by all instances within a sharing community. Therefore, for shared memory, the community itself is considered the owner.

Instance Resources  

Resources that are currently or permanently owned by a specific instance are displayed as children of the instance component.

Memory Assignment Chart  

The Memory Assignment chart illustrates the partitioning and assignment of memory fragments among the Galaxy instances. This chart displays both hardware components (arrays, controllers, and so on) and software components (memory fragments).

Current Galaxy firmware and operating system software does not support dynamic reconfiguration of memory. Therefore, the Memory Assignment chart reflects the way the memory address space has been partitioned by the console among the Galaxy instances. This information can be useful for debugging system applications or for studying possible configuration changes.

The following sections discuss memory fragments.

Console Fragments  

The console requires one or more small fragments of memory. Typically, a console allocates approximately 2 MB of memory in the low address range of each partition. This varies by hardware platform and firmware revision. Additionally, some consoles allocate a small fragment in high address space for each partition to store memory bitmaps. The console firmware may need to create additional fragments to enforce proper memory alignment.

Private Fragments  

Each Galaxy instance is required to have at least 64 MB of private memory (including the console fragments) to boot OpenVMS. This memory can consist of a single fragment, or the console firmware may need to create additional private fragments to enforce proper memory alignment.

Shared Memory Fragments  

To create an OpenVMS Galaxy, a minimum of 8 MB of shared memory must be allocated. This means the minimum memory requirement for an OpenVMS Galaxy is actually 72 MB (64 MB for a single instance and 8 MB for shared memory).

CPU Assignment Chart  

The CPU Assignment chart displays the minimal number of components required to reassign CPUs among the Galaxy instances. This chart can be useful for working with very large Galaxy configurations.

Primary CPU  

Each primary CPU is displayed as an oval rather than a hexagon. This is a reminder that primary CPUs cannot be reassigned or stopped. If you attempt to drag and drop a primary CPU, the GCU displays an error message in its status bar and does not allow the operation to occur.

Secondary CPUs  

Secondary CPUs are displayed as hexagons. Secondary CPUs can be reassigned among instances in either the Logical Structure chart or the CPU Assignment chart. Drag and drop the CPU on the desired instance. If you drop a CPU on the same instance that currently owns it, the CPU stops and restarts.

Fast Path and Affinitized CPUs  

If you reassign a CPU that has a Fast Path device currently affinitized to the CPU, the affinity device moves to another CPU and the CPU reassignment succeeds. If a CPU has a current process affinity assignment, the CPU cannot be reassigned.

For more information about using OpenVMS Fast Path features, see the HP OpenVMS I/O User's Reference Manual.

Lost CPUs  

You can reassign secondary CPUs to instances that are not yet booted (partitions).

Similarly, you can reassign a CPU to an instance that is not configured as a member of the Galaxy sharing community. In this case, you can push the CPU away from its current owner instance, but you cannot get it back unless you log in to the independent instance (a separate security domain) and reassign the CPU back to the current owner.

Regardless of whether an instance is part of the Galaxy sharing community or is an independent instance, it is still present in the Galaxy configuration file; therefore, the GCU is still able to display it.

IOP Assignment Chart  

The IOP Assignment chart displays the current relationship between I/O modules and the Galaxy instances. Note that, depending on what type of hardware platform is being used, a single-instance Galaxy on any Alpha system may not show any I/O modules in this display.

Failover Target Chart  

The Failover Target chart shows how each processor automatically fails over to other instances in the event of a shutdown or failure. Additionally, this chart illustrates the state of each CPU's autostart flag.

For each instance, a set of failover objects are shown, representing the full set of potential CPUs. By default, no failover relationships are established and all autostart flags are set.

To establish automatic failover of specific CPUs, drag and drop the desired failover object to the instance you want the associated CPU to target. To set failover relationships for all CPUs owned by an instance, drag and drop the instance object on top of the instance you want the CPUs to target.

To clear individual failover targets, drag and drop a failover object back to its owner instance. To clear all failover relationships, right-click on the instance object to display the Parameters &Commands dialog box, click on the Commands button, click the "Clear ALL failover targets?", button and then click OK.

By default, whenever a failover operation occurs, the CPUs automatically start once they arrive in the target instance. You can control this autostart function using the autostart commands found in the Parameters & Commands dialog box for each failover object, or each instance object. The Failover Target chart displays the state of the autostart flag by displaying the failover objects in green if autostart is set, and red if autostart is clear.

Please note the following restrictions in the current implementation of failover and autostart management:


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