In addition to the WebSphere metrics that up.time collects, detailed system level performance metrics are also available. This enables you to analyze system compute performance, memory usage, disk and network performance, and then relate underlying system behavior to specific metrics within WebSphere.
up.time collects metrics from WebSphere objects called modules. A module represents a resource category for which data is collected by the WebSphere Performance Management Infrastructure. Each module has at least one XML configuration file that lists a unique identifier for each piece of performance data contained in the module.
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