WebSphere® Application Server Hypervisor Edition Intelligent Management Pack is built
on features of autonomic computing in the dynamic operations environment.
With these features, the virtualized application server environment
can expand and contract as the business demands. Using the autonomic
managers in the product environment, dynamic operations can make logical
decisions based on business goals.
The dynamic operations environment has the following components:
- Operational policy
- An operational policy is a business, or performance objective
that supports specific goals for specific requests. Operational policies
include service and health policies. A service policy defines a business
goal and an importance and contains one or more transaction classes.
For a given work class, a rule condition maps to a transaction class
which belongs to a service policy. The service policy contains the
business goal requirements and the work class contains the work description
upon which the service policy is applicable. The combination of these
policies is read by the dynamic operations environment to make decisions
on HTTP, SOAP, JMS, SIP, and IIOP work
requests.
- Dynamic clusters
- A dynamic cluster is an application deployment target that is
expandable and contractible, as needed by the dynamic operations environment.
Dynamic clusters provide the core functionality of application infrastructure
virtualization. Dynamic cluster
instances are created on nodes that meet the criteria of a membership
policy that you specify when you create the dynamic cluster.
- Autonomic request flow manager
- The autonomic request flow manager (ARFM) has numerous functions:
- Uses queuing of incoming messages in edge-based gateways to provide
computing power overload protection and differentiated service. The
computing resource protected from overload is typically CPU power.
The differentiated service aims to provide the best balanced performance
results among various flows of traffic, relative to the given operational
policy and current offered load.
- Can optionally exert dialog/session-oriented admission control
for the sake of computing power overload protection.
- Sends information to the placement controller about each cluster
to enable the placement controller to optimize the placement for the
operational policy and currently offered load. The information about
a given cluster is the relationship between computing power and service
utility for that cluster.
- On demand router
- On demand router (ODRs) are intelligent HTTP proxies
and/or a SIP proxy. ODRs are the point of entry into a product
environment and are gateways through which HTTP requests and SIP messages flow to back-end application
servers. It can momentarily queue requests for less important applications
in order to allow request from more important applications to be handled
more quickly or to protect back-end application servers from being
overloaded. The ODR is aware of the current location of a dynamic
cluster's server's instances, so that requests can be routed to the
correct endpoint. The ODR can also dynamically adjust the amount of
traffic sent to each individual server instance based on process utilization
and response times. Note that for an inbound UDP message,an inbound SIP/UDP message, the ODR might
route the message to another ODR in order to properly check for and
handle UDP retransmission.
- Dynamic workload manager
- The autonomic request flow manager classifies and prioritizes
requests to application servers based on the demand and policies.
The dynamic workload manager then distributes the requests among the
nodes in a dynamic cluster to balance the work.
- Application placement controller
- The application placement controller is an autonomic manager in
the dynamic operations infrastructure that supports application virtualization,
or the fluid mobility of applications within a dynamic cluster. The
application placement controller adds application server instances
when the work is more than can be handled by the current application,
and stops application servers when there are too few requests for
the number of started applications.
- Health controller
- The health controller constantly monitors the defined health policies.
When a condition specified by a health policy is not met in the environment,
the health controller assures that the configured actions are taken
to correct the problem.
- EWLM
- The enterprise workload manager (EWLM) manages sub-goals and resource
allocations for the larger environment which contains the product.