Understanding HP WebQoS

The Role and Benefits of HP WebQoS

This is controlled by the WebQoS policies. When new sessions are rejected, redirected, or deferred, existing sessions continue uninterrupted. User request prioritization and session management are the primary tools used by WebQoS to provide capacity protection. The network manager is responsible for updating the timers that define a session, and for establishing the policies that control if the session is admitted.

Capacity Protection

Capacity Protection prevents system overload with prioritization and admission control. This minimizes the impact of unexpected surges in demand while maximizing the volume of completed transactions.

Capacity Protection makes sure that performance levels for active customers and their currently running transactions are not compromised. New user requests are not admitted to a site unless their transactions can be completed quickly.

Capacity is assessed by service level objectives and thresholds. Protection is provided by corrective actions.

SLOs, Thresholds, and Corrective Actions

To ensure that your business policies are reflected in your Web applications, they need to be translated into service level objectives (SLOs) and thresholds. SLOs are business-oriented policies and thresholds are operations-oriented policies. When an SLO or threshold is violated, a configured corrective action is performed.

SLOs WebQoS has the following types of business-oriented SLOs:

Capacity - Maximum number of concurrent sessions supportable with acceptable performance. Typically coupled with a response time SLO or performance threshold.

Response times - A key component of customer satisfaction. Measured from the time a request enters the server to the time a response is sent back.

External measurement - Measurements collected from external sources can be used to determine corrective actions.

Thresholds WebQoS uses an operations-oriented load threshold to keep your system operating properly during times of peak load. System load is assessed as a function of CPU (central processing unit) usage.

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HP WebQoS Software manual Capacity Protection, SLOs, Thresholds, and Corrective Actions