Dynamic operations

Intelligent Management increases the quality of service by monitoring the virtualized application server environment, and by making workload management optimizations or recommendations based on observed data. This capability is referred to as dynamic operations.

Increasingly, businesses are rigidly tied to the availability and speed of applications that deliver essential services to customers. Loss of availability translates into lost business, which means lost opportunity and lost revenue. Dynamic operations is a fluid and dynamic environment, supporting the continuous availability of applications through application server virtualization and application virtualization, the dynamic placement of applications, prioritization and flow control of work to the applications, and integrating with overall dynamic operations infrastructure management.

In a typical WebSphere® Application Server environment, there are sometimes static islands of dedicated resources to particular applications. This static structure leads to an inefficient use of resources. Some servers are not used to their full capability, and other servers are overloaded.

In a typical WebSphere Application Server environment, applications are statically mapped to a set of application servers. This configuration can be problematic because the percentage of utilized servers for one application can be very high, while unused resources are available that have been mapped to other applications. — Figure 1. Typical WebSphere Application Server environment

Intelligent Management supports a far more flexible environment using its dynamic operations features. Dynamic operations consists of autonomic managers that maximize utilization using defined business goals. These autonomic managers monitor performance metrics, analyze the monitored data, offer a plan for running actions, and can start these actions in response to the flow of work.

In an Intelligent Management environment, all of the servers are pooled together, which can even the distribution of workload among applications in the cell. — Figure 2. Intelligent Management environment

Intelligent Management offers the following autonomic managers as part of the dynamic operation functionality:

Autonomic request flow manager: Controls the order of requests into the application server tier and the rate of request flows. Using classification and the defined service goals, the autonomic request flow manager (ARFM) decides how and when to dispatch HTTP requests to the next tier. The ARFM also decides when Java™ Message Service (JMS) requests are dispatched at the application server tier, even though JMS requests are not routed through the ODR. For Internet Inter-ORB Protocol (IIOP) traffic that originates from stand-alone Enterprise JavaBeans (EJB) clients, ARFM also decides when the requests are dispatched at the application server tier, even though IIOP traffic is not routed through the ODR. For IIOP traffic that originates from EJB clients embedded within a servlet, a web service, or another EJB, the requests are dispatched immediately because traffic associated with the same overall user request must not be prioritized at multiple tiers, such as the Web tier and EJB tier.
Dynamic workload manager (DWLM): Performs load balancing across available application servers. In particular, for a given request flow, DWLM balances requests across the available nodes to regulate response times. DWLM dynamically updates the application status as the application placement controller modifies a running application infrastructure.
Application placement controller: Creates and removes application instances to manage HTTP, SIP, and IIOP traffic. The application placement controller can dynamically address periods of intense workflow that otherwise require the manual intervention of a system administrator. For IIOP requests, only standalone EJB clients are supported.
Health management: Maintains a robust application server environment using a health policy to identify the criteria that require action. When the criteria is met, action is taken to ensure that the environment remains healthy.

Autonomic managers with the on demand router (ODR) are the primary functional parts of dynamic operations. An ODR can be defined and started before any service policies are defined, but operational policies can be defined before the appearance of the work to which they apply. However, if policies are not defined, the early work is handled by the default policies. When work enters the ODR, an optimization effort achieves a balance of performance results. As the work flows, the dynamic workload manager balances the load. As work variations change and the balance of work in the nodes is upset, the application placement controller, autonomic request flow manager, and the dynamic workload manager rebalance running applications to ensure efficient work flows.

The combination of these autonomic managers provides a seamless, end-to-end dynamic runtime ability.

For transitioning users: In WebSphere Virtual Enterprise, controllers start automatically as highly available managed items unless explicitly suppressed. In Intelligent Management, controllers are dormant until they detect that they are needed. When the controllers are needed, they become active. When the controllers detect that they are no longer needed, they become dormant again. Controllers that are disabled or are in manual mode do not use this detection capability.