Pathway/XM System Management Manual

Pathway/XM Benefits and Features
Compaq NonStop™ Pathway/XM System Management Manual—426761-001
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Automatic Load Balancing of Requester and Server
Processes
external TCPs, external PATHMON processes, or associative servers. If separate
management is required for multiple applications, multiple Pathway/XM environments
can run on the same set of Compaq NonStop™ Himalaya systems.
In addition, the abstraction provided by logical configurations allows your application to
grow easily. Pathway/XM can automatically add more instances of processes and tasks
that you have already defined.
Automatic Load Balancing of Requester and Server
Processes
Pathway/XM simplifies the tuning of your applications by providing automatic load
balancing, through replication and distribution of the processes that support terminals
(TCPs) and of server classes.
Transaction requests to servers are balanced on a per-transaction basis. System
workload is automatically rebalanced when a processor fails or is reloaded.
The Pathway/XM configuration interface allows you to define the system resources
(Expand nodes and processors) to be used for load balancing of requester and servers.
Online Reconfiguration of Server Classes
Distributed server classes can be temporarily deactivated—for example, for online
replacement of servers—without shutting down the application. You can suspend
operation of a server class, change many configured values (including the distribution of
system and CPU resources), and then resume its operation. While the server class is
suspended, transaction requests are queued so that they can be serviced as soon as the
server class is back online.
Predefined Server Classes
Pathway/XM supports the distribution of third-party Pathway/XM configurations of
server classes using an export/import mode. You can generate node-independent server
class configurations (SERVICE objects) from your current SuperCTL file, ready for
export to customers.
To import server class configurations (from a third party application, for example), you
configure predefined temporary server classes (SERVICE objects). When server class
configurations are imported, Pathway/XM uses your predefined SERVICE object values
to establish relationships with nodes, apply filename substitutions relevant to your
environment, and generate group name relationships to the newly imported server
classes. Once the server classes are imported, you use the server names or their group
names to manage the server processes.