9.1 GCU Tour
The GCU can perform three types of operations:
* Create of Galaxy configuration models or a single-
instance Galaxy.
* Observe active Galaxy performance and resources.
* Interact with active Galaxy resource configurations.
Most GCU operations are organized around the main ob-
servation window and its hierarchical display of Galaxy
components. The observation window provides a porthole into
a very large space. The observation window can be panned
and zoomed as needed to observe part or the entire Galaxy
configuration. The main toolbar contains a set of buttons that
control workspace zoom operations. Workspace panning is
controlled by the horizontal and vertical scrollbars; workspace
sliding is achieved by holding down the middle mouse but-
ton down as you drag the workspace around. This obviously
assumes you have a three-button mouse.
The various GCU operations are invoked from pull down or
popup menu functions. General operations such as opening
and closing files, and invoking external tools, are accom-
plished using the main menu bar entries. Operations specific
to individual Galaxy components are accomplished using
popup menus that appear whenever you click the right
mouse button on a component displayed in the observation
window.
In response to many operations, the GCU displays addi-
tional dialog boxes containing information, forms, editors, or
prompts. Error and information responses are displayed in
popup dialog boxes or inside the status bar along the bottom
of the window, depending on the severity of the error and
importance of the message.
9.1.1 Creating Galaxy Configuration Models
You can use the GCU to create Galaxy configuration models
and a single-instance Galaxy on any Alpha system.
When viewing the active Galaxy configuration model, direct
manipulation of display objects (components) may alter the
running configuration. For example, dragging a CPU com-
ponent from its current location and dropping it on top of a
different instance component will invoke a management ac-
tion procedure, that reassigns the selected CPU to the new
instance. At certain times this may be a desirable operation;
however, in other situations you might want to reconfigure
your Galaxy all at once rather than component by compo-
nent. To accomplish this, you must create an offline Galaxy
configuration model.
To create a Galaxy configuration model, we must start with
an existing model, typically the active one, alter it in some
manner, and save it in a file.
Starting from the active Galaxy Configuration Model:
1. Press the ENGAGE button such that the model becomes
DISENGAGED. The button should turn from red to white,
and its appearance should be popped outward. When dis-
engaged, all CPU components in the display will turn
red as an indication that they are no longer engaged. Do
not panic, they have not been shutdown! The model has
simply been taken off-line.
2. Alter the CPU assignments by dragging and dropping in-
dividual CPUs on top of the instances you wish to assign
them to.
3. When finished, you can either re-engage the model, or
save the model in a file for later use. Whenever you re-
engage a model, regardless of whether the model was
derived from the active model or from a file-based model,
the GCU will compare the active system configuration
with the configuration proposed by the model. It will then
provide a summary of management actions that would
need to be performed to reassign the system to the new
model. If the user approves of the actions, the GCU will
commence with execution of the required management
actions and the resulting model will be displayed as the
active and engaged model.
The reason for creating offline models is to allow significant
configuration changes to be automated. For example, you can
create models representing the desired Galaxy configuration
at different times and then engage the models interactively
by following this procedure.
9.1.2 Observation
The GCU can display the single active Galaxy configuration
model, or any number of offline Galaxy configuration models.
Each loaded model appears as an item in the Model menu on
the toolbar. You can switch between models by clicking the
desired menu item.
The active model is always named GLX$ACTIVE.GCM.
When the active model is first loaded, a file by this name will
exist briefly as the system synchronizes the model with the
system hardware.
When a model is visible, you can zoom, pan, or slide the dis-
play as needed to view Galaxy components. Use the buttons
on the left side of the toolbar to control the zoom functions.
The zoom functions include:
Galactic zoom Zoom to fit the entire component hierarchy
into observation window.
Zoom 1:1 Zoom to the component normal scale.
Zoom to region Zoom to a selected region of the display.
Zoom in Zoom in by 10 percent.
Zoom out Zoom out by 10 percent.
Panning is accomplished by using the vertical and horizontal
scrollbars. Sliding is done by pressing and holding the mid-
dle mouse button and dragging (sliding) the cursor and the
image.
9.1.2.1 Layout Management
The Automatic Layout feature manages the component lay-
out. If you ever need to refresh the layout while in Automatic
Layout mode, simply select the root (topmost) component.
To alter the current layout, select Manual Layout from the
Windows menu. In Manual Layout Mode, you can freely
drag and drop components however you like to generate a
pleasing structure. Because each component is free from
automatic layout constraints, you may need to invest some
time in positioning each component, possibly on each of the
charts. To make things simpler, you can click press the right
mouse button on any component and select Layout Subtree
to provide automatic layout assistance below that point in the
hierarchy.
When you are satisfied with the layout, you must save the
current model in a file to retain the manual layout infor-
mation. The custom layout is used when the model is open.
Note that if you select Auto Layout mode, your manual lay-
out will be lost for the in-memory model. Also, in order for
CPU components to reassign in a visually effective manner,
they must perform subtree layout operations below the in-
stance level. For this reason, it is best to limit any manual
layout operations to the instance and community levels of the
component hierarchy.
9.1.2.2 OpenVMS Galaxy Charts
The GCU provides six distinct subsets of the model, known as
charts.
The six charts include:
Chart name Shows
Logical Structure Dynamic resource assignments
Physical Structure Nonvolatile hardware relationships
CPU Assignment Simplified view of CPU assignments
Memory Assignment Memory subsystem components
IOP Assignment I/O processor relationships
Failover Targets Processor failover assignments
These charts result from enabling or disabling the display of
various component types to provide views of sensible subsets
of components.
Specific charts may offer functionality that can be pro-
vided only for that chart type. For example, reassignment
of CPUs requires that the instance components be visible.
Because instances are not visible in the Physical Structure or
Memory Assignment charts, you can reassign CPUs only in
the Logical Structure and CPU Assignment charts.
For more information about charts, refer to Section 9.4.
9.1.3 Interaction
When viewing the active Galaxy configuration model, you
can interact directly with the system components. For exam-
ple, to reassign a CPU from one instance to another, you can
drag and drop a CPU onto the desired instance. The GCU
will validate the operation and execute an external command
action to make the configuration change. Interacting with a
model that is not engaged, is simply a drawing operation on
the offline model, and has no impact to the running system.
While interacting with Galaxy components, the GCU applies
built-in and user-defined rules that prevent misconfiguration
and improper management actions. For example, you cannot
reassign primary CPUs, and you cannot reassign a CPU to
any component other than a Galaxy instance. Either opera-
tion would result in an error message on the status bar, and
the model would return to its proper configuration. If the at-
tempted operation violates one of the configuration rules, the
error message, displayed in red on the status bar, will describe
the rule that fired.
You can view details for any selected component by clicking
the right mouse button and either selecting the Parameters
item from the popup menu or by selecting Parameters from
the Components menu on the main toolbar.
The GCU can shut down or reboot one or more Galaxy in-
stances using the Shutdown or Reboot items on the Galaxy
menu. The various shutdown or reboot parameters can be
entered in the Shutdown dialog box. Be sure to specify the
CLUSTER_SHUTDOWN option to fully shut down clustered
Galaxy instances. The Shutdown dialog box allows you to se-
lect any combination of instances, or all instances. The GCU
is ``smart'' enough to shut down its owner instance last.